diff --git a/client/src/components/Chart.tsx b/client/src/components/Chart.tsx
new file mode 100644
index 0000000..773e7f4
--- /dev/null
+++ b/client/src/components/Chart.tsx
@@ -0,0 +1,60 @@
+import React from 'react';
+import { LineChart, Line, BarChart, Bar, XAxis, YAxis, CartesianGrid, Tooltip, Legend, ResponsiveContainer } from 'recharts';
+
+interface ChartProps {
+  title: string;
+  data: any[];
+  type: 'line' | 'bar';
+  dataKey: string;
+  stroke?: string;
+  fill?: string;
+  height?: number;
+}
+
+function Chart({
+  title,
+  data,
+  type,
+  dataKey,
+  stroke = '#667eea',
+  fill = '#667eea',
+  height = 300,
+}: ChartProps) {
+  if (!data || data.length === 0) {
+    return (
+      <div className="chart-container">
+        <h4>{title}</h4>
+        <div className="chart-placeholder">暂无数据</div>
+      </div>
+    );
+  }
+
+  return (
+    <div className="chart-container">
+      <h4>{title}</h4>
+      <ResponsiveContainer width="100%" height={height}>
+        {type === 'line' ? (
+          <LineChart data={data}>
+            <CartesianGrid strokeDasharray="3 3" />
+            <XAxis dataKey="date" fontSize={12} />
+            <YAxis fontSize={12} />
+            <Tooltip />
+            <Legend />
+            <Line type="monotone" dataKey={dataKey} stroke={stroke} dot={{ r: 4 }} />
+          </LineChart>
+        ) : (
+          <BarChart data={data}>
+            <CartesianGrid strokeDasharray="3 3" />
+            <XAxis dataKey="date" fontSize={12} />
+            <YAxis fontSize={12} />
+            <Tooltip />
+            <Legend />
+            <Bar dataKey={dataKey} fill={fill} />
+          </BarChart>
+        )}
+      </ResponsiveContainer>
+    </div>
+  );
+}
+
+export default Chart;
diff --git a/client/src/pages/Dashboard.css b/client/src/pages/Dashboard.css
new file mode 100644
index 0000000..456f608
--- /dev/null
+++ b/client/src/pages/Dashboard.css
@@ -0,0 +1,162 @@
+.today-summary,
+.statistics {
+  margin-bottom: 2rem;
+}
+
+.today-summary h3,
+.statistics h3,
+.charts-section h3 {
+  font-size: 1.2rem;
+  color: #333;
+  margin-bottom: 1rem;
+}
+
+.stats-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
+  gap: 1rem;
+  margin-bottom: 2rem;
+}
+
+.stat-card {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+  background: white;
+  border: 1px solid #eee;
+  border-radius: 8px;
+  padding: 1rem;
+  transition: all 0.3s ease;
+  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
+}
+
+.stat-card:hover {
+  border-color: #667eea;
+  box-shadow: 0 4px 12px rgba(102, 126, 234, 0.1);
+  transform: translateY(-2px);
+}
+
+.stat-icon {
+  font-size: 2rem;
+  flex-shrink: 0;
+}
+
+.stat-content {
+  flex: 1;
+}
+
+.stat-label {
+  font-size: 0.85rem;
+  color: #999;
+  font-weight: 600;
+  text-transform: uppercase;
+  letter-spacing: 0.5px;
+  margin-bottom: 0.25rem;
+}
+
+.stat-value {
+  font-size: 1.4rem;
+  font-weight: 700;
+  color: #333;
+}
+
+.charts-section {
+  margin-top: 2rem;
+}
+
+.charts-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
+  gap: 1.5rem;
+  margin-bottom: 2rem;
+}
+
+.chart-container {
+  background: white;
+  border: 1px solid #eee;
+  border-radius: 8px;
+  padding: 1rem;
+  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
+}
+
+.chart-container h4 {
+  margin-top: 0;
+  margin-bottom: 1rem;
+  font-size: 1rem;
+  color: #333;
+}
+
+.chart-placeholder {
+  height: 300px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  color: #ccc;
+  font-size: 1rem;
+  background: #f9f9f9;
+  border-radius: 4px;
+}
+
+.page-loading {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  min-height: 400px;
+  font-size: 1.2rem;
+  color: #666;
+}
+
+.error-message {
+  background: #fee;
+  border: 1px solid #fcc;
+  color: #c33;
+  padding: 1rem;
+  border-radius: 8px;
+  margin-bottom: 1rem;
+  font-size: 0.95rem;
+}
+
+.placeholder {
+  text-align: center;
+  padding: 2rem;
+  color: #999;
+  background: #f9f9f9;
+  border-radius: 8px;
+  font-size: 1rem;
+}
+
+@media (max-width: 768px) {
+  .stats-grid {
+    grid-template-columns: repeat(2, 1fr);
+  }
+
+  .charts-grid {
+    grid-template-columns: 1fr;
+  }
+
+  .stat-value {
+    font-size: 1.2rem;
+  }
+}
+
+@media (max-width: 480px) {
+  .stats-grid {
+    grid-template-columns: 1fr;
+  }
+
+  .stat-card {
+    padding: 0.75rem;
+  }
+
+  .stat-icon {
+    font-size: 1.5rem;
+  }
+
+  .stat-label {
+    font-size: 0.75rem;
+  }
+
+  .stat-value {
+    font-size: 1rem;
+  }
+}
diff --git a/client/src/pages/Dashboard.tsx b/client/src/pages/Dashboard.tsx
index 2164422..364406a 100644
--- a/client/src/pages/Dashboard.tsx
+++ b/client/src/pages/Dashboard.tsx
@@ -1,33 +1,216 @@
 import React, { useEffect, useState } from 'react';
 import { apiClient } from '../services/api';
-import './Pages.css';
+import Chart from '../components/Chart';
+import './Dashboard.css';
+
+interface HealthData {
+  date: string;
+  steps?: number;
+  heartRate?: number;
+  sleep?: {
+    duration: number;
+    quality: number;
+  };
+  caloriesBurned?: number;
+}
 
 function Dashboard() {
   const [loading, setLoading] = useState(true);
-  const [summary, setSummary] = useState<any>(null);
+  const [error, setError] = useState<string>('');
+  const [summary, setSummary] = useState<HealthData[]>([]);
+  const [today, setToday] = useState<HealthData | null>(null);
+  const [stats, setStats] = useState({
+    avgSteps: 0,
+    avgHeartRate: 0,
+    avgSleep: 0,
+    totalCalories: 0,
+  });
 
   useEffect(() => {
-    const loadData = async () => {
-      try {
-        // TODO: Fetch health summary data
-        setLoading(false);
-      } catch (error) {
-        console.error('Failed to load summary:', error);
-        setLoading(false);
-      }
-    };
-
     loadData();
   }, []);
 
+  const loadData = async () => {
+    try {
+      setLoading(true);
+      setError('');
+
+      // Load 30-day summary
+      const now = new Date();
+      const thirtyDaysAgo = new Date(now.getTime() - 30 * 24 * 60 * 60 * 1000);
+
+      const startDate = thirtyDaysAgo.toISOString().split('T')[0];
+      const endDate = now.toISOString().split('T')[0];
+
+      const response = await apiClient.getHealthSummary(startDate, endDate);
+      const data = response.data.data || [];
+
+      setSummary(data);
+
+      // Get today's data
+      const todayData = data.find((d: HealthData) => d.date === endDate);
+      setToday(todayData || null);
+
+      // Calculate stats
+      const validData = data.filter((d: HealthData) => d.steps || d.heartRate);
+      if (validData.length > 0) {
+        const avgSteps =
+          Math.round(
+            validData.reduce((sum: number, d: HealthData) => sum + (d.steps || 0), 0) /
+              validData.length
+          ) || 0;
+
+        const heartRates = validData
+          .map((d: HealthData) => d.heartRate)
+          .filter((hr) => hr);
+        const avgHeartRate =
+          heartRates.length > 0
+            ? Math.round(heartRates.reduce((a, b) => a + b, 0) / heartRates.length)
+            : 0;
+
+        const sleeps = validData
+          .map((d: HealthData) => d.sleep?.duration)
+          .filter((s) => s);
+        const avgSleep =
+          sleeps.length > 0
+            ? Math.round((sleeps.reduce((a, b) => a + b, 0) / sleeps.length) * 10) / 10
+            : 0;
+
+        const totalCalories = Math.round(
+          validData.reduce((sum: number, d: HealthData) => sum + (d.caloriesBurned || 0), 0)
+        );
+
+        setStats({ avgSteps, avgHeartRate, avgSleep, totalCalories });
+      }
+
+      setLoading(false);
+    } catch (err: any) {
+      const errorMsg = err.response?.data?.error?.message || 'Failed to load data';
+      setError(errorMsg);
+      setLoading(false);
+    }
+  };
+
   if (loading) {
-    return <div className="page-loading">加载中...</div>;
+    return <div className="page-loading">⏳ 加载中...</div>;
   }
 
   return (
     <div className="page">
-      <h2>健康仪表板</h2>
-      <p className="placeholder">仪表板内容即将推出...</p>
+      <h2>📊 健康仪表板</h2>
+
+      {error && <div className="error-message">{error}</div>}
+
+      {/* Today's Summary */}
+      {today ? (
+        <div className="today-summary">
+          <h3>今日概览</h3>
+          <div className="stats-grid">
+            <div className="stat-card">
+              <div className="stat-icon">🚶</div>
+              <div className="stat-content">
+                <div className="stat-label">步数</div>
+                <div className="stat-value">{today.steps || '-'}</div>
+              </div>
+            </div>
+
+            <div className="stat-card">
+              <div className="stat-icon">❤️</div>
+              <div className="stat-content">
+                <div className="stat-label">心率</div>
+                <div className="stat-value">{today.heartRate || '-'} bpm</div>
+              </div>
+            </div>
+
+            <div className="stat-card">
+              <div className="stat-icon">😴</div>
+              <div className="stat-content">
+                <div className="stat-label">睡眠</div>
+                <div className="stat-value">{today.sleep?.duration || '-'} 小时</div>
+              </div>
+            </div>
+
+            <div className="stat-card">
+              <div className="stat-icon">🔥</div>
+              <div className="stat-content">
+                <div className="stat-label">卡路里</div>
+                <div className="stat-value">{today.caloriesBurned || '-'} kcal</div>
+              </div>
+            </div>
+          </div>
+        </div>
+      ) : (
+        <div className="placeholder">暂无今日数据</div>
+      )}
+
+      {/* 30-Day Statistics */}
+      <div className="statistics">
+        <h3>30 日统计</h3>
+        <div className="stats-grid">
+          <div className="stat-card">
+            <div className="stat-icon">📈</div>
+            <div className="stat-content">
+              <div className="stat-label">平均步数</div>
+              <div className="stat-value">{stats.avgSteps.toLocaleString()}</div>
+            </div>
+          </div>
+
+          <div className="stat-card">
+            <div className="stat-icon">❤️</div>
+            <div className="stat-content">
+              <div className="stat-label">平均心率</div>
+              <div className="stat-value">{stats.avgHeartRate} bpm</div>
+            </div>
+          </div>
+
+          <div className="stat-card">
+            <div className="stat-icon">😴</div>
+            <div className="stat-content">
+              <div className="stat-label">平均睡眠</div>
+              <div className="stat-value">{stats.avgSleep}h</div>
+            </div>
+          </div>
+
+          <div className="stat-card">
+            <div className="stat-icon">🔥</div>
+            <div className="stat-content">
+              <div className="stat-label">总卡路里消耗</div>
+              <div className="stat-value">{stats.totalCalories.toLocaleString()}</div>
+            </div>
+          </div>
+        </div>
+      </div>
+
+      {/* Charts */}
+      {summary.length > 0 && (
+        <div className="charts-section">
+          <h3>数据趋势</h3>
+          <div className="charts-grid">
+            <Chart title="步数" data={summary} type="bar" dataKey="steps" fill="#667eea" />
+            <Chart
+              title="心率"
+              data={summary.filter((d) => d.heartRate)}
+              type="line"
+              dataKey="heartRate"
+              stroke="#ff6b9d"
+            />
+            <Chart
+              title="睡眠时长"
+              data={summary.filter((d) => d.sleep)}
+              type="line"
+              dataKey={(d: any) => d.sleep?.duration}
+              stroke="#ffd93d"
+            />
+            <Chart
+              title="卡路里消耗"
+              data={summary}
+              type="bar"
+              dataKey="caloriesBurned"
+              fill="#6bcf7f"
+            />
+          </div>
+        </div>
+      )}
     </div>
   );
 }
diff --git a/client/src/pages/DataSync.css b/client/src/pages/DataSync.css
new file mode 100644
index 0000000..ce83b6e
--- /dev/null
+++ b/client/src/pages/DataSync.css
@@ -0,0 +1,155 @@
+.sync-container {
+  display: grid;
+  gap: 2rem;
+  max-width: 600px;
+  margin: 0 auto;
+}
+
+.subtitle {
+  color: #666;
+  font-size: 1rem;
+  margin-top: -0.5rem;
+  margin-bottom: 1.5rem;
+}
+
+.status-card {
+  background: white;
+  border: 1px solid #eee;
+  border-radius: 8px;
+  padding: 1.5rem;
+  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
+}
+
+.status-card h3 {
+  margin-top: 0;
+  margin-bottom: 1rem;
+  color: #333;
+  font-size: 1.1rem;
+}
+
+.status-info {
+  display: flex;
+  flex-direction: column;
+  gap: 1rem;
+}
+
+.status-item {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 0.75rem;
+  background: #f9f9f9;
+  border-radius: 6px;
+  font-size: 0.95rem;
+}
+
+.status-item.error {
+  background: #fee;
+  border: 1px solid #fcc;
+}
+
+.status-item .label {
+  font-weight: 600;
+  color: #666;
+}
+
+.status-item .value {
+  color: #333;
+  font-weight: 500;
+}
+
+.sync-actions {
+  display: flex;
+  flex-direction: column;
+  gap: 1rem;
+  align-items: center;
+}
+
+.btn-large {
+  width: 100%;
+  max-width: 300px;
+  padding: 1rem 2rem;
+  font-size: 1.1rem;
+}
+
+.help-text {
+  text-align: center;
+  color: #999;
+  font-size: 0.9rem;
+  max-width: 400px;
+  line-height: 1.5;
+}
+
+.error-message,
+.success-message {
+  padding: 1rem;
+  border-radius: 8px;
+  font-size: 0.95rem;
+  animation: slideIn 0.3s ease-out;
+}
+
+.error-message {
+  background: #fee;
+  border: 1px solid #fcc;
+  color: #c33;
+}
+
+.success-message {
+  background: #efe;
+  border: 1px solid #cfc;
+  color: #333;
+}
+
+@keyframes slideIn {
+  from {
+    opacity: 0;
+    transform: translateY(-10px);
+  }
+  to {
+    opacity: 1;
+    transform: translateY(0);
+  }
+}
+
+.info-box {
+  background: #f0f7ff;
+  border: 1px solid #d0e8ff;
+  border-radius: 8px;
+  padding: 1.5rem;
+}
+
+.info-box h4 {
+  margin-top: 0;
+  margin-bottom: 1rem;
+  color: #333;
+  font-size: 1rem;
+}
+
+.info-box ul {
+  margin: 0;
+  padding-left: 1.5rem;
+  list-style: disc;
+  color: #666;
+  line-height: 1.8;
+}
+
+.info-box li {
+  margin-bottom: 0.5rem;
+  font-size: 0.9rem;
+}
+
+@media (max-width: 768px) {
+  .sync-container {
+    gap: 1.5rem;
+  }
+
+  .status-item {
+    flex-direction: column;
+    align-items: flex-start;
+    gap: 0.5rem;
+  }
+
+  .btn-large {
+    max-width: 100%;
+  }
+}
diff --git a/client/src/pages/DataSync.tsx b/client/src/pages/DataSync.tsx
index 2d56e9f..89c2d7a 100644
--- a/client/src/pages/DataSync.tsx
+++ b/client/src/pages/DataSync.tsx
@@ -1,18 +1,161 @@
-import React from 'react';
-import './Pages.css';
+import React, { useEffect, useState } from 'react';
+import { apiClient } from '../services/api';
+import './DataSync.css';
+
+interface SyncStatus {
+  status: 'idle' | 'syncing' | 'error';
+  lastSyncTime: string | null;
+  recordsSynced: number;
+  lastError?: string;
+}
 
 function DataSync() {
+  const [syncStatus, setSyncStatus] = useState<SyncStatus | null>(null);
+  const [loading, setLoading] = useState(false);
+  const [error, setError] = useState<string>('');
+  const [message, setMessage] = useState<string>('');
+
+  // Load sync status on component mount
+  useEffect(() => {
+    loadSyncStatus();
+  }, []);
+
+  const loadSyncStatus = async () => {
+    try {
+      const response = await apiClient.getGarminSyncStatus();
+      setSyncStatus(response.data.data);
+    } catch (err: any) {
+      console.error('Failed to load sync status:', err);
+    }
+  };
+
   const handleSync = async () => {
-    // TODO: Implement data sync
+    setLoading(true);
+    setError('');
+    setMessage('');
+
+    try {
+      const response = await apiClient.syncGarminData();
+
+      if (response.data.success) {
+        setMessage(`✅ 同步完成！新增/更新 ${response.data.data.recordsSynced} 天数据`);
+        // Reload sync status
+        loadSyncStatus();
+      } else {
+        setError(`❌ 同步失败：${response.data.data.message}`);
+      }
+    } catch (err: any) {
+      const errorMsg = err.response?.data?.error?.message || 'Sync failed';
+      setError(`❌ 同步失败：${errorMsg}`);
+    } finally {
+      setLoading(false);
+    }
+  };
+
+  const getStatusColor = (status: string) => {
+    switch (status) {
+      case 'idle':
+        return '#999';
+      case 'syncing':
+        return '#667eea';
+      case 'error':
+        return '#c33';
+      default:
+        return '#999';
+    }
+  };
+
+  const getStatusText = (status: string) => {
+    switch (status) {
+      case 'idle':
+        return '就绪';
+      case 'syncing':
+        return '正在同步...';
+      case 'error':
+        return '同步失败';
+      default:
+        return '未知';
+    }
   };
 
   return (
     <div className="page">
-      <h2>数据同步</h2>
-      <p className="placeholder">数据同步功能即将推出...</p>
-      <button onClick={handleSync} className="btn btn-primary">
-        同步 Garmin 数据
-      </button>
+      <h2>📱 数据同步</h2>
+      <p className="subtitle">从 Garmin Connect 同步你的健康数据</p>
+
+      <div className="sync-container">
+        {/* Status Card */}
+        <div className="status-card">
+          <h3>同步状态</h3>
+
+          {syncStatus ? (
+            <div className="status-info">
+              <div className="status-item">
+                <span className="label">状态</span>
+                <span
+                  className="value"
+                  style={{ color: getStatusColor(syncStatus.status) }}
+                >
+                  {getStatusText(syncStatus.status)}
+                </span>
+              </div>
+
+              {syncStatus.lastSyncTime && (
+                <div className="status-item">
+                  <span className="label">最后同步</span>
+                  <span className="value">
+                    {new Date(syncStatus.lastSyncTime).toLocaleString('zh-CN')}
+                  </span>
+                </div>
+              )}
+
+              <div className="status-item">
+                <span className="label">已同步数据</span>
+                <span className="value">{syncStatus.recordsSynced} 天</span>
+              </div>
+
+              {syncStatus.lastError && (
+                <div className="status-item error">
+                  <span className="label">错误信息</span>
+                  <span className="value">{syncStatus.lastError}</span>
+                </div>
+              )}
+            </div>
+          ) : (
+            <p className="placeholder">加载中...</p>
+          )}
+        </div>
+
+        {/* Sync Button */}
+        <div className="sync-actions">
+          <button
+            onClick={handleSync}
+            disabled={loading || (syncStatus?.status === 'syncing')}
+            className="btn btn-primary btn-large"
+          >
+            {loading || syncStatus?.status === 'syncing' ? '✋ 正在同步...' : '🔄 立即同步'}
+          </button>
+
+          <p className="help-text">
+            数据同步会获取你最近 7 天的 Garmin 健康数据，包括步数、心率、睡眠、运动等信息。
+          </p>
+        </div>
+
+        {/* Messages */}
+        {error && <div className="error-message">{error}</div>}
+        {message && <div className="success-message">{message}</div>}
+
+        {/* Info Box */}
+        <div className="info-box">
+          <h4>💡 关于数据同步</h4>
+          <ul>
+            <li>首次同步会获取你最近 7 天的数据</li>
+            <li>之后同步会增量更新最新的数据</li>
+            <li>数据会保存到本地数据库</li>
+            <li>同步频率受 Garmin API 限制</li>
+          </ul>
+        </div>
+      </div>
     </div>
   );
 }