diff --git a/API.md b/API.md
index 801be9e..97012f8 100644
--- a/API.md
+++ b/API.md
@@ -45,6 +45,9 @@ Content-Type: application/json
 | `leftLabel` | string | — | `"左侧"` | 左侧区域标签 |
 | `rightLabel` | string | — | `"右侧"` | 右侧区域标签 |
 | `splitStyle` | string | — | `"solid"` | 分割线样式：`solid` / `dashed` / `dotted` |
+| `dualYAxis` | boolean | — | `false` | 启用双Y轴（左右量度不同） |
+| `rightAxisSeries` | array | — | `null` | 右轴系列名列表，如 `["利润"]`（未列出的系列用左轴） |
+| `rightAxisName` | string | — | `""` | 右轴名称 |
 | `width` | number | — | `800` | 图片宽度（px） |
 | `height` | number | — | `500` | 图片高度（px） |
 | `pixelRatio` | number | — | `2` | 像素倍率（越大越清晰） |
diff --git a/README.md b/README.md
index 19c3d9e..2078a43 100644
--- a/README.md
+++ b/README.md
@@ -11,6 +11,7 @@
 - **柱状图** - 支持单系列/多系列对比
 - **折线图** - 支持平滑曲线、面积填充
 - **混合图** - 柱状图+折线图组合展示
+- **双Y轴** - 一张图左右两个坐标轴，量度可不同，系列可指定左轴/右轴（含右轴名称）
 
 ### 📋 表格功能
 - **表格图片生成** - 根据数据生成精美的表格图片
diff --git a/app.js b/app.js
index 1a1c63d..dc38e12 100644
--- a/app.js
+++ b/app.js
@@ -3,6 +3,7 @@ let chartInstance = null;
 let parsedData = null;
 let seriesColors = [];
 let seriesOrder = [];
+let seriesAxis = []; // 每个系列所属轴：0=左轴 1=右轴
 let currentMode = 'chart'; // 'chart' or 'table'
 let tableImageBlob = null;
 
@@ -131,6 +132,7 @@ function generateChart() {
     seriesOrder = parsedData.seriesNames.map((_, i) => i);
     const palette = colorPalettes[document.getElementById('themeStyle').value] || colorPalettes.default;
     seriesColors = parsedData.seriesNames.map((_, i) => palette[i % palette.length]);
+    seriesAxis = parsedData.seriesNames.map(() => 0);
 
     // 渲染系列配置
     renderSeriesConfig();
@@ -172,6 +174,8 @@ function updateChart() {
     const stackMode = document.getElementById('stackMode').checked;
     const smoothLine = document.getElementById('smoothLine').checked;
     const enableSplit = document.getElementById('enableSplit').checked;
+    const dualAxis = document.getElementById('dualAxis').checked;
+    const rightAxisName = document.getElementById('rightAxisName').value;
 
     // 显示/隐藏分割配置
     document.getElementById('splitConfig').style.display = enableSplit ? 'block' : 'none';
@@ -248,6 +252,11 @@ function updateChart() {
             };
         }
 
+        // 双Y轴：按系列指定左右轴
+        if (dualAxis) {
+            seriesItem.yAxisIndex = (seriesAxis[origIdx] === 1) ? 1 : 0;
+        }
+
         return seriesItem;
     });
 
@@ -379,7 +388,30 @@ function updateChart() {
             },
             axisTick: { show: false }
         },
-        yAxis: {
+        yAxis: dualAxis ? [
+            {
+                type: 'value',
+                name: '左轴',
+                nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 0, 0, 4] },
+                axisLine: { show: false },
+                axisTick: { show: false },
+                axisLabel: { color: textColor, fontSize: 11 },
+                splitLine: {
+                    show: showGrid,
+                    lineStyle: { color: theme === 'dark' ? '#333' : '#f0f0f0', type: 'dashed' }
+                }
+            },
+            {
+                type: 'value',
+                name: rightAxisName || '右轴',
+                position: 'right',
+                nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 4, 0, 0] },
+                axisLine: { show: false },
+                axisTick: { show: false },
+                axisLabel: { color: textColor, fontSize: 11 },
+                splitLine: { show: false }
+            }
+        ] : {
             type: 'value',
             axisLine: { show: false },
             axisTick: { show: false },
@@ -466,6 +498,13 @@ function renderSeriesConfig() {
     seriesOrder.forEach((origIdx, displayIdx) => {
         const name = parsedData.seriesNames[origIdx];
         const color = seriesColors[origIdx];
+        const dualAxis = document.getElementById('dualAxis').checked;
+        const axisSelect = dualAxis ? `
+            <select onchange="updateSeriesAxis(${origIdx}, this.value)" title="所属坐标轴">
+                <option value="0" ${seriesAxis[origIdx] === 0 ? 'selected' : ''}>左轴</option>
+                <option value="1" ${seriesAxis[origIdx] === 1 ? 'selected' : ''}>右轴</option>
+            </select>
+        ` : '';
 
         const item = document.createElement('div');
         item.className = 'series-item';
@@ -481,6 +520,7 @@ function renderSeriesConfig() {
                 <option value="bar">柱状</option>
                 <option value="line">折线</option>
             </select>
+            ${axisSelect}
         `;
 
         // 拖拽事件
@@ -566,6 +606,19 @@ function updateSeriesType(origIdx, type) {
     updateChart();
 }
 
+// ===== 双Y轴 =====
+function onDualAxisChange() {
+    const on = document.getElementById('dualAxis').checked;
+    document.getElementById('rightAxisGroup').style.display = on ? 'block' : 'none';
+    renderSeriesConfig(); // 显示/隐藏系列轴选择
+    updateChart();
+}
+
+function updateSeriesAxis(origIdx, axis) {
+    seriesAxis[origIdx] = parseInt(axis) || 0;
+    updateChart();
+}
+
 // ===== 工具函数 =====
 function adjustColor(hex, amount) {
     hex = hex.replace('#', '');
diff --git a/index.html b/index.html
index 5b1e549..937a29d 100644
--- a/index.html
+++ b/index.html
@@ -100,8 +100,15 @@ C, 20, 30, 40</pre>
                             <label><input type="checkbox" id="showLabel" onchange="updateChart()"> 数据标签</label>
                             <label><input type="checkbox" id="stackMode" onchange="updateChart()"> 堆叠模式</label>
                             <label><input type="checkbox" id="smoothLine" checked onchange="updateChart()"> 平滑曲线</label>
+                            <label><input type="checkbox" id="dualAxis" onchange="onDualAxisChange()"> 双Y轴</label>
                         </div>
                     </div>
+
+                    <div class="config-group" id="rightAxisGroup" style="display:none;">
+                        <label>右轴名称（量度不同）</label>
+                        <input type="text" id="rightAxisName" placeholder="如：利润(万元)" oninput="updateChart()">
+                        <p class="hint-text">在下方「系列配置」中可指定每个系列用左轴/右轴</p>
+                    </div>
                 </div>
 
                 <!-- 表格配置区 -->
diff --git a/server.js b/server.js
index efbb292..8a2bbcb 100644
--- a/server.js
+++ b/server.js
@@ -113,7 +113,10 @@ function buildChartOption(params) {
         leftLabel = '左侧',
         rightLabel = '右侧',
         splitStyle = 'solid',
-        seriesColors: customColors = null
+        seriesColors: customColors = null,
+        dualYAxis = false,
+        rightAxisSeries = null,
+        rightAxisName = ''
     } = params;
 
     const parsedData = parseData(data);
@@ -148,6 +151,12 @@ function buildChartOption(params) {
             }
         };
 
+        // 双Y轴：rightAxisSeries 指定右轴系列名
+        if (dualYAxis) {
+            const rightNames = Array.isArray(rightAxisSeries) ? rightAxisSeries : (rightAxisSeries ? [rightAxisSeries] : []);
+            seriesItem.yAxisIndex = rightNames.includes(name) ? 1 : 0;
+        }
+
         if (stackMode) {
             seriesItem.stack = 'total';
         }
@@ -159,8 +168,7 @@ function buildChartOption(params) {
             seriesItem.areaStyle = theme === 'gradient' ? { opacity: 0.15 } : undefined;
         }
 
-        if (type === 'bar') {
-            seriesItem.barMaxWidth = 40;
+        if (type === 'bar') {seriesItem.barMaxWidth = 40;
             seriesItem.itemStyle.borderRadius = stackMode ? [0, 0, 0, 0] : [4, 4, 0, 0];
         }
 
@@ -269,7 +277,33 @@ function buildChartOption(params) {
             },
             axisTick: { show: false }
         },
-        yAxis: {
+        yAxis: dualYAxis ? [
+            {
+                type: 'value',
+                name: '左轴',
+                nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 0, 0, 4] },
+                axisLine: { show: false },
+                axisTick: { show: false },
+                axisLabel: { color: textColor, fontSize: 11 },
+                splitLine: {
+                    show: showGrid,
+                    lineStyle: {
+                        color: theme === 'dark' ? '#333' : '#f0f0f0',
+                        type: 'dashed'
+                    }
+                }
+            },
+            {
+                type: 'value',
+                name: rightAxisName || '右轴',
+                position: 'right',
+                nameTextStyle: { color: textColor, fontSize: 11, padding: [0, 4, 0, 0] },
+                axisLine: { show: false },
+                axisTick: { show: false },
+                axisLabel: { color: textColor, fontSize: 11 },
+                splitLine: { show: false }
+            }
+        ] : {
             type: 'value',
             axisLine: { show: false },
             axisTick: { show: false },
@@ -366,6 +400,9 @@ app.get('/api/chart', (req, res) => {
             leftLabel: req.query.leftLabel || '左侧',
             rightLabel: req.query.rightLabel || '右侧',
             splitStyle: req.query.splitStyle || 'solid',
+            dualYAxis: req.query.dualYAxis === 'true',
+            rightAxisSeries: req.query.rightAxisSeries ? req.query.rightAxisSeries.split(',') : null,
+            rightAxisName: req.query.rightAxisName || '',
             width: parseInt(req.query.width) || 800,
             height: parseInt(req.query.height) || 500,
             format: req.query.format || 'png',
@@ -882,7 +919,7 @@ app.get('/api/health', (req, res) => {
     res.json({
         status: 'ok',
         service: 'data-chart-tool',
-        version: '1.10.1',
+        version: '1.11.0',
         endpoints: {
             'POST /api/chart': '生成图表图片（JSON body）',
             'GET /api/chart': '生成图表图片（URL 参数）',
@@ -897,7 +934,7 @@ app.get('/api/health', (req, res) => {
 app.get('/api/docs', (req, res) => {
     res.json({
         name: '数据可视化图表生成器 API',
-        version: '1.10.1',
+        version: '1.11.0',
         endpoints: [
             {
                 method: 'POST',
@@ -922,7 +959,10 @@ app.get('/api/docs', (req, res) => {
                     width: { type: 'number', default: 800, description: '图片宽度(px)' },
                     height: { type: 'number', default: 500, description: '图片高度(px)' },
                     format: { type: 'string', default: 'png', options: ['png'], description: '输出格式' },
-                    pixelRatio: { type: 'number', default: 2, description: '像素倍率（清晰度）' }
+                    pixelRatio: { type: 'number', default: 2, description: '像素倍率（清晰度）' },
+                    dualYAxis: { type: 'boolean', default: false, description: '是否启用双Y轴（左右量度不同）' },
+                    rightAxisSeries: { type: 'array', default: null, description: '右轴系列名列表（如 ["利润"]，指定哪些系列用右轴）' },
+                    rightAxisName: { type: 'string', default: '', description: '右轴名称' }
                 },
                 returns: 'image/png',
                 example: {
diff --git a/style.css b/style.css
index 069fc44..4aa34de 100644
--- a/style.css
+++ b/style.css
@@ -719,6 +719,14 @@ input[type="range"]::-moz-range-thumb {
 }
 
 .btn-sm {
-    padding: 6px 12px;
-    font-size: 0.82rem;
+    padding: 4px 10px;
+    font-size: 0.78rem;
+}
+
+/* 导出设置折叠栏下载按钮（更小，避免挤占） */
+.export-header .btn-sm {
+    padding: 3px 8px;
+    font-size: 0.74rem;
+    white-space: nowrap;
+    flex-shrink: 0;
 }