diff --git a/package.json b/package.json
index 5bfe668..570b38f 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "waveform-analysis",
-  "version": "0.1.29",
+  "version": "0.1.30",
   "main": "./dist/index.cjs",
   "module": "./dist/index.js",
   "types": "./dist/types/index.d.ts",
diff --git a/src/App.vue b/src/App.vue
index ec27c22..b03177d 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -14,6 +14,7 @@ import {
   type WaveformLegendOrientation,
   type WaveformLegendPosition,
   type WaveformOverlayMode,
+  type WaveformPlotMargin,
   type WaveformTitleOptions,
   type WaveformZoomEndPayload,
   type WaveformZeroLineOptions,
@@ -47,6 +48,8 @@ const annotationsVisible = ref(true)
 const cleanView = ref(false)
 const presentationMode = ref(false)
 const showTooltip = ref(true)
+const plotMarginTop = ref(18)
+const plotMarginBottom = ref(52)
 const zeroLineVisible = ref(false)
 const zeroLineColor = ref('#98a2b3')
 const zeroLineWidth = ref(1)
@@ -126,6 +129,10 @@ const zeroLine = computed<WaveformZeroLineOptions>(() => ({
   width: zeroLineWidth.value,
   dash: zeroLineDash.value,
 }))
+const plotMargin = computed<WaveformPlotMargin>(() => ({
+  top: plotMarginTop.value,
+  bottom: plotMarginBottom.value,
+}))
 
 const initialXValues = normalizeWaveformSeries(fullChartData).flatMap((series) =>
   series.points.map((point) => point.x),
@@ -294,6 +301,8 @@ const controlPanelModel = reactive({
   displayMode,
   overlayMode,
   showTooltip,
+  plotMarginTop,
+  plotMarginBottom,
   cleanView,
   presentationMode,
   selectedSeriesId,
@@ -360,6 +369,7 @@ const chartModel = reactive({
   cleanView,
   presentationMode,
   showTooltip,
+  plotMargin,
   zeroLine,
   frameWatermarkVisible,
   annotations,
diff --git a/src/components/WaveformChart.vue b/src/components/WaveformChart.vue
index 3ab8475..3594fa6 100644
--- a/src/components/WaveformChart.vue
+++ b/src/components/WaveformChart.vue
@@ -23,6 +23,7 @@ const props = withDefaults(defineProps<WaveformChartProps>(), {
   interactionMode: undefined,
   grid: () => ({ rowCount: 2, columnCount: 1, showPagination: true }),
   rendering: () => ({}),
+  plotMargin: () => ({}),
   legend: () => ({ position: 'top-right', orientation: 'auto' }),
   defaultHiddenSeriesIds: () => [],
   cleanView: false,
diff --git a/src/components/WaveformChartView.vue b/src/components/WaveformChartView.vue
index 6423482..116e089 100644
--- a/src/components/WaveformChartView.vue
+++ b/src/components/WaveformChartView.vue
@@ -19,6 +19,7 @@ const {
   overlayMode,
   resolvedChartLeftMargin,
   titleAreaHeight,
+  resolvedPlotMargin,
   pointerInsideChart,
   handleNativeContextMenu,
   titleAreaReserved,
@@ -118,6 +119,8 @@ const {
     :data-presentation-mode="isPresentationMode"
     :data-overlay-mode="overlayMode"
     :data-chart-left-margin="resolvedChartLeftMargin"
+    :data-plot-margin-top="resolvedPlotMargin.top"
+    :data-plot-margin-bottom="resolvedPlotMargin.bottom"
     :data-title-area-height="titleAreaHeight"
     @pointerenter="pointerInsideChart = true"
     @pointerleave="pointerInsideChart = false"
@@ -287,18 +290,18 @@ const {
             />
           </g>
         </g>
-
-        <text
-          v-if="resolvedXLabel && !isCleanView"
-          class="waveform-chart__label waveform-chart__x-label"
-          :x="innerWidth / 2"
-          :y="xAxisTitleY"
-          text-anchor="middle"
-        >
-          {{ resolvedXLabel }}
-        </text>
       </g>
 
+      <text
+        v-if="resolvedXLabel && !isCleanView"
+        class="waveform-chart__label waveform-chart__x-label"
+        :x="resolvedChartLeftMargin + innerWidth / 2"
+        :y="xAxisTitleY"
+        text-anchor="middle"
+      >
+        {{ resolvedXLabel }}
+      </text>
+
       <text
         v-if="hasChartArea && !hasWaveformData"
         class="waveform-chart__empty"
diff --git a/src/components/core/constants.ts b/src/components/core/constants.ts
index 798b62a..e0efae3 100644
--- a/src/components/core/constants.ts
+++ b/src/components/core/constants.ts
@@ -7,6 +7,9 @@
 /** 图表边距 */
 export const margin = { top: 18, right: 24, bottom: 52, left: 64 }
 
+/** Distance from the drawing SVG bottom edge to the X-axis title baseline. */
+export const X_AXIS_TITLE_BOTTOM_OFFSET = 12
+
 /**
  * 图表最小高度（像素）
  */
diff --git a/src/components/core/useWaveformLayout.ts b/src/components/core/useWaveformLayout.ts
index 505fb41..4874f0b 100644
--- a/src/components/core/useWaveformLayout.ts
+++ b/src/components/core/useWaveformLayout.ts
@@ -24,7 +24,6 @@ import {
   normalizeGridOptions,
   paginateSeries,
   resolveGridCellGeometry,
-  X_AXIS_BAND,
 } from './grid'
 import {
   buildTrackLayouts,
@@ -316,7 +315,6 @@ export function useWaveformLayout(context: LayoutContext) {
         )
       : [],
   )
-  const xAxisTitleY = computed(() => innerHeight.value + X_AXIS_BAND + 10)
   const editorSeries = computed<AnnotationSeriesInfo | undefined>(() => {
     const seriesId = annotationInteraction.editorDraft.value?.annotation.seriesId
     const series = chartSeries.value.find((item) => item.id === seriesId)
@@ -360,7 +358,6 @@ export function useWaveformLayout(context: LayoutContext) {
     resolveSeriesYScale,
     annotationTrackLayouts,
     renderedAnnotations,
-    xAxisTitleY,
     editorSeries,
     resolveFrameNumber,
   }
diff --git a/src/components/core/useWaveformPresentation.ts b/src/components/core/useWaveformPresentation.ts
index 7ab7949..c390186 100644
--- a/src/components/core/useWaveformPresentation.ts
+++ b/src/components/core/useWaveformPresentation.ts
@@ -7,6 +7,7 @@ import {
   TITLE_CHAR_WIDTH_RATIO,
   TITLE_DEFAULT_FONT_SIZE,
   TITLE_LINE_HEIGHT,
+  X_AXIS_TITLE_BOTTOM_OFFSET,
   ZERO_LINE_DEFAULTS,
 } from './constants'
 import { calculateRotatedTitleLayout, TITLE_AREA_HORIZONTAL_PADDING } from './title'
@@ -144,11 +145,23 @@ export function useWaveformPresentation(context: PresentationContext) {
   const titleAreaHeight = computed(() =>
     titleAreaReserved.value ? titleLayout.value.areaHeight : 0,
   )
-  const chartTopMargin = computed(() => margin.top)
+  const resolvePlotMargin = (value: number | undefined, fallback: number) =>
+    typeof value === 'number' && Number.isFinite(value) && value >= 0 ? value : fallback
+  const resolvedPlotMargin = computed(() => ({
+    top: resolvePlotMargin(props.plotMargin.top, margin.top),
+    bottom: resolvePlotMargin(props.plotMargin.bottom, margin.bottom),
+  }))
+  const chartTopMargin = computed(() => resolvedPlotMargin.value.top)
   const drawingHeight = computed(() =>
     Math.max(0, chartHeight.value - titleAreaHeight.value - paginationBandHeight.value),
   )
-  const innerHeight = computed(() => Math.max(0, drawingHeight.value - margin.top - margin.bottom))
+  const xAxisTitleY = computed(() => Math.max(0, drawingHeight.value - X_AXIS_TITLE_BOTTOM_OFFSET))
+  const innerHeight = computed(() =>
+    Math.max(
+      0,
+      drawingHeight.value - resolvedPlotMargin.value.top - resolvedPlotMargin.value.bottom,
+    ),
+  )
   const titleAreaStyle = computed<CSSProperties>(() => ({
     height: `${titleAreaHeight.value}px`,
     justifyContent:
@@ -193,8 +206,10 @@ export function useWaveformPresentation(context: PresentationContext) {
     titleMeasureStyle,
     titleLayout,
     titleAreaHeight,
+    resolvedPlotMargin,
     chartTopMargin,
     drawingHeight,
+    xAxisTitleY,
     innerHeight,
     titleAreaStyle,
     titleVisualStyle,
diff --git a/src/components/core/waveformChartTypes.ts b/src/components/core/waveformChartTypes.ts
index 448b2b6..6582322 100644
--- a/src/components/core/waveformChartTypes.ts
+++ b/src/components/core/waveformChartTypes.ts
@@ -7,6 +7,7 @@ import type {
   WaveformInteractionMode,
   WaveformLegendOptions,
   WaveformOverlayMode,
+  WaveformPlotMargin,
   WaveformPoint,
   WaveformRenderingOptions,
   WaveformTitleOptions,
@@ -42,6 +43,7 @@ export interface WaveformChartProps {
   interactionMode?: WaveformInteractionMode
   grid?: WaveformGridOptions
   rendering?: WaveformRenderingOptions
+  plotMargin?: WaveformPlotMargin
   title?: WaveformTitleOptions
   legend?: WaveformLegendOptions
   hiddenSeriesIds?: string[]
@@ -65,6 +67,7 @@ type DefaultedProp =
   | 'annotationsVisible'
   | 'grid'
   | 'rendering'
+  | 'plotMargin'
   | 'legend'
   | 'defaultHiddenSeriesIds'
   | 'cleanView'
diff --git a/src/components/data/types.ts b/src/components/data/types.ts
index 6b29381..ea360c4 100644
--- a/src/components/data/types.ts
+++ b/src/components/data/types.ts
@@ -13,6 +13,7 @@ export type {
   WaveformAnnotationStyle,
   WaveformAnnotation,
   WaveformRenderingOptions,
+  WaveformPlotMargin,
   WaveformTitleTextStyle,
   WaveformTitleOptions,
   WaveformLegendPosition,
diff --git a/src/components/index.ts b/src/components/index.ts
index a9090c9..0d35862 100644
--- a/src/components/index.ts
+++ b/src/components/index.ts
@@ -11,6 +11,7 @@ export type {
   WaveformAnnotationStyle,
   WaveformAnnotation,
   WaveformRenderingOptions,
+  WaveformPlotMargin,
   WaveformTitleTextStyle,
   WaveformTitleOptions,
   WaveformLegendPosition,
diff --git a/src/components/waveform.ts b/src/components/waveform.ts
index 7edab65..8b34811 100644
--- a/src/components/waveform.ts
+++ b/src/components/waveform.ts
@@ -12,6 +12,7 @@ export type {
   WaveformAnnotationStyle,
   WaveformAnnotation,
   WaveformRenderingOptions,
+  WaveformPlotMargin,
   WaveformTitleTextStyle,
   WaveformTitleOptions,
   WaveformFrameStyle,
diff --git a/src/components/waveformChartCases/sizingAndTitles.test.ts b/src/components/waveformChartCases/sizingAndTitles.test.ts
index 15c65ab..b22f548 100644
--- a/src/components/waveformChartCases/sizingAndTitles.test.ts
+++ b/src/components/waveformChartCases/sizingAndTitles.test.ts
@@ -105,6 +105,65 @@ describe('WaveformChart', () => {
     expect(wrapper.get('.waveform-chart__svg').attributes('height')).toBe('300')
   })
 
+  it('configures plot top and bottom margins and reacts to updates', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        plotMargin: { top: 30, bottom: 70 },
+      },
+    )
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('30')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('70')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('260')
+    expect(wrapper.get('.waveform-chart__svg > g').attributes('transform')).toContain(', 30)')
+
+    await wrapper.setProps({ plotMargin: { top: 12 } })
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('12')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('52')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('296')
+  })
+
+  it('falls back to default plot margins for invalid values', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        plotMargin: { top: -1, bottom: Number.NaN },
+      },
+    )
+
+    expect(wrapper.attributes('data-plot-margin-top')).toBe('18')
+    expect(wrapper.attributes('data-plot-margin-bottom')).toBe('52')
+    expect(wrapper.get('.waveform-chart__overlay').attributes('height')).toBe('290')
+  })
+
+  it('keeps the chart title and X-axis title fixed when plot margins change', async () => {
+    const wrapper = await mountSizedChart(
+      { kind: 'samples', values: [0, 1], sampleRate: 1 },
+      {
+        displayMode: 'compact',
+        grid: { rowCount: 1, columnCount: 1 },
+        title: { text: '固定标题' },
+      },
+    )
+    const titleAreaStyle = wrapper.get('.waveform-chart__title-area').attributes('style')
+    const xAxisTitle = wrapper.get('.waveform-chart__x-label')
+    const initialX = xAxisTitle.attributes('x')
+    const initialY = xAxisTitle.attributes('y')
+
+    await wrapper.setProps({ plotMargin: { top: 60, bottom: 90 } })
+
+    expect(wrapper.get('.waveform-chart__title-area').attributes('style')).toBe(titleAreaStyle)
+    expect(wrapper.get('.waveform-chart__x-label').attributes('x')).toBe(initialX)
+    expect(wrapper.get('.waveform-chart__x-label').attributes('y')).toBe(initialY)
+    expect(wrapper.get('.waveform-chart__svg > g').attributes('transform')).toContain(', 60)')
+  })
+
   it('does not render or reserve space for missing, hidden, or blank titles', async () => {
     for (const title of [undefined, { visible: false, text: '隐藏标题' }, { text: '   ' }]) {
       const wrapper = await mountSizedChart(
diff --git a/src/demo/DemoChartHost.vue b/src/demo/DemoChartHost.vue
index 52d138e..dd0ee76 100644
--- a/src/demo/DemoChartHost.vue
+++ b/src/demo/DemoChartHost.vue
@@ -45,6 +45,7 @@ defineExpose({ resetViewport })
       :clean-view="model.cleanView"
       :presentation-mode="model.presentationMode"
       :show-tooltip="model.showTooltip"
+      :plot-margin="model.plotMargin"
       :zero-line="model.zeroLine"
       :frame-number="model.frameWatermarkVisible ? 1 : undefined"
       :annotations-visible="model.annotationsVisible"
diff --git a/src/demo/DemoGridFrameControls.vue b/src/demo/DemoGridFrameControls.vue
index f0f13f6..0ca926f 100644
--- a/src/demo/DemoGridFrameControls.vue
+++ b/src/demo/DemoGridFrameControls.vue
@@ -8,6 +8,35 @@ const model = defineModel<DemoControlPanelModel>('model', { required: true })
 </script>
 
 <template>
+  <section class="control-section">
+    <h2>绘图区边距</h2>
+    <div class="plot-margin-controls">
+      <label class="frame-style-control">
+        <span>上边距</span>
+        <InputNumber
+          v-model:value="model.plotMarginTop"
+          :min="0"
+          :max="300"
+          :step="1"
+          addon-after="px"
+          size="small"
+          aria-label="绘图区上边距"
+        />
+      </label>
+      <label class="frame-style-control">
+        <span>下边距</span>
+        <InputNumber
+          v-model:value="model.plotMarginBottom"
+          :min="0"
+          :max="300"
+          :step="1"
+          addon-after="px"
+          size="small"
+          aria-label="绘图区下边距"
+        />
+      </label>
+    </div>
+  </section>
   <section class="control-section">
     <div class="control-section__header">
       <h2>零值参考线</h2>
diff --git a/src/demo/plotMarginControls.test.ts b/src/demo/plotMarginControls.test.ts
new file mode 100644
index 0000000..e7e46d1
--- /dev/null
+++ b/src/demo/plotMarginControls.test.ts
@@ -0,0 +1,29 @@
+import { flushPromises, mount } from '@vue/test-utils'
+import { InputNumber } from 'ant-design-vue'
+import { describe, expect, it } from 'vitest'
+
+import App from '../App.vue'
+import { WaveformChart } from '../components'
+
+describe('plot margin demo controls', () => {
+  it('updates the chart top and bottom margins from the sidebar', async () => {
+    const wrapper = mount(App)
+    await flushPromises()
+    const chart = wrapper.getComponent(WaveformChart)
+    const controls = wrapper.get('.plot-margin-controls').findAllComponents(InputNumber)
+
+    expect(controls).toHaveLength(2)
+    expect(controls[0]?.props('value')).toBe(18)
+    expect(controls[1]?.props('value')).toBe(52)
+    expect(chart.props('plotMargin')).toEqual({ top: 18, bottom: 52 })
+
+    controls[0]?.vm.$emit('update:value', 30)
+    controls[1]?.vm.$emit('update:value', 70)
+    await flushPromises()
+
+    expect(chart.props('plotMargin')).toEqual({ top: 30, bottom: 70 })
+    expect(wrapper.get('.waveform-chart').attributes('data-plot-margin-top')).toBe('30')
+    expect(wrapper.get('.waveform-chart').attributes('data-plot-margin-bottom')).toBe('70')
+    wrapper.unmount()
+  })
+})
diff --git a/src/demo/types.ts b/src/demo/types.ts
index 8cc3b67..2ad32c5 100644
--- a/src/demo/types.ts
+++ b/src/demo/types.ts
@@ -10,6 +10,7 @@ import type {
   WaveformLegendPosition,
   WaveformLineStyle,
   WaveformOverlayMode,
+  WaveformPlotMargin,
   WaveformTitleOptions,
   WaveformZeroLineOptions,
   WaveformZoomEndPayload,
@@ -26,6 +27,8 @@ export interface DemoControlPanelModel {
   displayMode: WaveformDisplayMode
   overlayMode: WaveformOverlayMode
   showTooltip: boolean
+  plotMarginTop: number
+  plotMarginBottom: number
   cleanView: boolean
   presentationMode: boolean
   selectedSeriesId: string
@@ -99,6 +102,7 @@ export interface DemoChartModel {
   cleanView: boolean
   presentationMode: boolean
   showTooltip: boolean
+  plotMargin: WaveformPlotMargin
   zeroLine: WaveformZeroLineOptions
   frameWatermarkVisible: boolean
   annotations: WaveformAnnotation[]
diff --git a/src/index.ts b/src/index.ts
index 4cd8b7f..d5812f2 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -17,6 +17,7 @@ export type {
   WaveformAnnotationStyle,
   WaveformAnnotation,
   WaveformRenderingOptions,
+  WaveformPlotMargin,
   WaveformTitleTextStyle,
   WaveformTitleOptions,
   WaveformLegendPosition,
diff --git a/src/styles.css b/src/styles.css
index ac3feac..9a1c8c6 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -195,6 +195,7 @@ body {
 }
 
 .frame-style-controls,
+.plot-margin-controls,
 .auxiliary-style-controls {
   display: grid;
   gap: 10px;
diff --git a/src/types/chart.ts b/src/types/chart.ts
index 68cb48d..610c087 100644
--- a/src/types/chart.ts
+++ b/src/types/chart.ts
@@ -74,6 +74,14 @@ export interface WaveformRenderingOptions {
   errorBarMinSpacing?: number
 }
 
+/** Pixel margins reserved above and below the waveform plotting area. */
+export interface WaveformPlotMargin {
+  /** Space between the top of the drawing SVG and the plotting area. Defaults to 18. */
+  top?: number
+  /** Space between the plotting area and the bottom of the drawing SVG. Defaults to 52. */
+  bottom?: number
+}
+
 /** Text styling for the chart-level title. */
 export interface WaveformTitleTextStyle {
   color?: string
diff --git a/src/types/index.ts b/src/types/index.ts
index 0adc13b..7dd1fa5 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -12,6 +12,7 @@ export type {
   WaveformAnnotationStyle,
   WaveformAnnotation,
   WaveformRenderingOptions,
+  WaveformPlotMargin,
   WaveformTitleTextStyle,
   WaveformTitleOptions,
   WaveformLegendPosition,