diff --git a/frontend/src/components/EChartsIntraday.tsx b/frontend/src/components/EChartsIntraday.tsx
index dae6b00..8b777da 100644
--- a/frontend/src/components/EChartsIntraday.tsx
+++ b/frontend/src/components/EChartsIntraday.tsx
@@ -30,7 +30,8 @@ interface Props {
   showAvgLine?: boolean
 }
 
-function fmtAmt(v: number): string {
+function fmtAmt(v: number | null | undefined): string {
+  if (v == null || !Number.isFinite(v)) return '—'
   if (v >= 1_000_000_000) return `${(v / 1_000_000_000).toFixed(2)}亿`
   if (v >= 10_000) return `${(v / 10_000).toFixed(0)}万`
   return v.toFixed(0)
diff --git a/frontend/src/components/EChartsMultiDayIntraday.tsx b/frontend/src/components/EChartsMultiDayIntraday.tsx
index 1db4dc3..8012726 100644
--- a/frontend/src/components/EChartsMultiDayIntraday.tsx
+++ b/frontend/src/components/EChartsMultiDayIntraday.tsx
@@ -29,7 +29,8 @@ interface InfoPoint {
   prevClose: number | null
 }
 
-function formatAmount(value: number): string {
+function formatAmount(value: number | null | undefined): string {
+  if (value == null || !Number.isFinite(value)) return '—'
   if (value >= 1_000_000_000) return `${(value / 1_000_000_000).toFixed(2)}亿`
   if (value >= 10_000) return `${(value / 10_000).toFixed(0)}万`
   return value.toFixed(0)
diff --git a/frontend/src/lib/api.ts b/frontend/src/lib/api.ts
index a5efd2d..0f20fa5 100644
--- a/frontend/src/lib/api.ts
+++ b/frontend/src/lib/api.ts
@@ -208,7 +208,7 @@ export interface MinuteKlineRow {
   low: number
   close: number
   volume: number
-  amount: number
+  amount: number | null
 }
 
 export interface MinuteKlineSession {
diff --git a/frontend/src/lib/intraday-chart.ts b/frontend/src/lib/intraday-chart.ts
index eac5aff..2d96c8f 100644
--- a/frontend/src/lib/intraday-chart.ts
+++ b/frontend/src/lib/intraday-chart.ts
@@ -11,10 +11,15 @@ export function computeIntradayAverage(data: MinuteKlineRow[]): number[] {
   const result: number[] = []
   let amount = 0
   let volume = 0
+  let hasAmount = true
   for (const row of data) {
-    amount += row.amount
+    if (typeof row.amount === 'number' && Number.isFinite(row.amount)) {
+      amount += row.amount
+    } else {
+      hasAmount = false
+    }
     volume += row.volume * 100
-    result.push(volume > 0 ? amount / volume : row.close)
+    result.push(hasAmount && volume > 0 ? amount / volume : row.close)
   }
   return result
 }