diff --git a/frontend/src/components/pages/AssistantPage.tsx b/frontend/src/components/pages/AssistantPage.tsx
index 578e81a..3ae5572 100644
--- a/frontend/src/components/pages/AssistantPage.tsx
+++ b/frontend/src/components/pages/AssistantPage.tsx
@@ -7,6 +7,8 @@ import {
   Check,
   Copy,
   Database,
+  Eye,
+  EyeOff,
   MessageSquareText,
   MoreHorizontal,
   Pencil,
@@ -525,7 +527,8 @@ export function AssistantPage() {
     setDifyForm({
       name: a.name,
       apiUrl: a.apiUrl,
-      apiKey: a.apiKey, // 编辑时为打码值,不改则原样回传(后端哨兵保留旧 key)
+      // 编辑时不把打码占位符放入输入框；空值写回后端表示保留旧 key
+      apiKey: "",
       asr: a.asrCredentialId ?? "",
       voice: a.ttsCredentialId ?? "",
       enableInterrupt: a.enableInterrupt,
@@ -552,7 +555,8 @@ export function AssistantPage() {
       name: a.name,
       appId: a.appId,
       apiUrl: a.apiUrl,
-      apiKey: a.apiKey,
+      // 编辑时不把打码占位符放入输入框；空值写回后端表示保留旧 key
+      apiKey: "",
       asr: a.asrCredentialId ?? "",
       voice: a.ttsCredentialId ?? "",
       enableInterrupt: a.enableInterrupt,
@@ -580,6 +584,9 @@ export function AssistantPage() {
     type: typeToLabel[a.type],
     updatedAt: formatTimestamp(a.updatedAt),
   }));
+  const hasStoredApiKey = Boolean(
+    editingId && assistants.find((assistant) => assistant.id === editingId)?.apiKey,
+  );
 
   const filteredAssistants = listItems.filter((assistant) => {
     if (typeFilter !== "全部" && assistant.type !== typeFilter) {
@@ -1082,6 +1089,7 @@ export function AssistantPage() {
       <div className="-mt-6 flex h-full flex-col gap-4">
         <div className="flex shrink-0 items-center justify-between gap-6 border-b border-hairline pb-3 pt-1">
           <div className="flex min-w-0 items-center gap-2">
+            <EditorBackButton onClick={() => setView("list")} />
             <EditableTitle
               value={difyForm.name}
               onChange={(value) => updateDifyForm("name", value)}
@@ -1089,15 +1097,6 @@ export function AssistantPage() {
           </div>
 
           <div className="flex shrink-0 gap-2">
-            <Button
-              variant="outline"
-              className="gap-2 border-hairline-strong text-muted-foreground hover:text-foreground"
-              onClick={() => setView("list")}
-            >
-              <ChevronLeft size={16} />
-              返回
-            </Button>
-
             {saveError && (
               <span className="self-center text-xs text-destructive">
                 {saveError}
@@ -1131,12 +1130,12 @@ export function AssistantPage() {
                 onChange={(value) => updateDifyForm("apiUrl", value)}
                 placeholder="https://api.dify.ai/v1/chat-messages"
               />
-              <InputField
+              <SecretInputField
                 label="API Key"
                 value={difyForm.apiKey}
                 onChange={(value) => updateDifyForm("apiKey", value)}
                 placeholder="请输入 Dify API Key"
-                type="password"
+                hasStoredValue={hasStoredApiKey}
               />
             </SectionCard>
 
@@ -1188,6 +1187,7 @@ export function AssistantPage() {
       <div className="-mt-6 flex h-full flex-col gap-4">
         <div className="flex shrink-0 items-center justify-between gap-6 border-b border-hairline pb-3 pt-1">
           <div className="flex min-w-0 items-center gap-2">
+            <EditorBackButton onClick={() => setView("list")} />
             <EditableTitle
               value={fastGptForm.name}
               onChange={(value) => updateFastGptForm("name", value)}
@@ -1195,15 +1195,6 @@ export function AssistantPage() {
           </div>
 
           <div className="flex shrink-0 gap-2">
-            <Button
-              variant="outline"
-              className="gap-2 border-hairline-strong text-muted-foreground hover:text-foreground"
-              onClick={() => setView("list")}
-            >
-              <ChevronLeft size={16} />
-              返回
-            </Button>
-
             {saveError && (
               <span className="self-center text-xs text-destructive">
                 {saveError}
@@ -1243,12 +1234,12 @@ export function AssistantPage() {
                 onChange={(value) => updateFastGptForm("apiUrl", value)}
                 placeholder="https://api.fastgpt.in/api/v1/chat/completions"
               />
-              <InputField
+              <SecretInputField
                 label="API Key"
                 value={fastGptForm.apiKey}
                 onChange={(value) => updateFastGptForm("apiKey", value)}
                 placeholder="请输入 FastGPT API Key"
-                type="password"
+                hasStoredValue={hasStoredApiKey}
               />
             </SectionCard>
 
@@ -1300,6 +1291,7 @@ export function AssistantPage() {
       <div className="-mt-6 flex h-full flex-col gap-4">
         <div className="flex shrink-0 items-center justify-between gap-6 border-b border-hairline pb-3 pt-1">
           <div className="flex min-w-0 items-center gap-2">
+            <EditorBackButton onClick={() => setView("list")} />
             <EditableTitle
               value={openCodeForm.name}
               onChange={(value) => updateOpenCodeForm("name", value)}
@@ -1307,15 +1299,6 @@ export function AssistantPage() {
           </div>
 
           <div className="flex shrink-0 gap-2">
-            <Button
-              variant="outline"
-              className="gap-2 border-hairline-strong text-muted-foreground hover:text-foreground"
-              onClick={() => setView("list")}
-            >
-              <ChevronLeft size={16} />
-              返回
-            </Button>
-
             <Button className="gap-2">
               <Save size={16} />
               保存
@@ -1336,12 +1319,12 @@ export function AssistantPage() {
                 onChange={(value) => updateOpenCodeForm("apiUrl", value)}
                 placeholder="http://localhost:4096"
               />
-              <InputField
+              <SecretInputField
                 label="API Key"
                 value={openCodeForm.apiKey}
                 onChange={(value) => updateOpenCodeForm("apiKey", value)}
                 placeholder="请输入 OpenCode API Key"
-                type="password"
+                hasStoredValue={false}
               />
             </SectionCard>
 
@@ -1403,6 +1386,7 @@ export function AssistantPage() {
     <div className="-mt-6 flex h-full flex-col gap-4">
       <div className="flex shrink-0 items-center justify-between gap-6 border-b border-hairline pb-3 pt-1">
         <div className="flex min-w-0 items-center gap-2">
+          <EditorBackButton onClick={() => setView("list")} />
           <EditableTitle
             value={form.name}
             onChange={(value) => updateForm("name", value)}
@@ -1410,15 +1394,6 @@ export function AssistantPage() {
         </div>
 
         <div className="flex shrink-0 gap-2">
-          <Button
-            variant="outline"
-            className="gap-2 border-hairline-strong text-muted-foreground hover:text-foreground"
-            onClick={() => setView("list")}
-          >
-            <ChevronLeft size={16} />
-            返回
-          </Button>
-
           {saveError && (
             <span className="self-center text-xs text-destructive">
               {saveError}
@@ -1754,6 +1729,20 @@ function DebugVoicePanel() {
   );
 }
 
+function EditorBackButton({ onClick }: { onClick: () => void }) {
+  return (
+    <Button
+      variant="ghost"
+      size="icon"
+      className="shrink-0 text-muted-foreground hover:text-foreground"
+      onClick={onClick}
+      aria-label="返回助手列表"
+    >
+      <ChevronLeft size={20} />
+    </Button>
+  );
+}
+
 function EditableTitle({
   value,
   onChange,
@@ -1915,6 +1904,60 @@ function InputField({
   );
 }
 
+function SecretInputField({
+  label,
+  value,
+  placeholder,
+  hasStoredValue,
+  onChange,
+}: {
+  label?: string;
+  value: string;
+  placeholder?: string;
+  hasStoredValue: boolean;
+  onChange: (value: string) => void;
+}) {
+  const [showValue, setShowValue] = useState(false);
+
+  return (
+    <label className="block">
+      {label && (
+        <div className="mb-2 text-sm font-medium text-foreground">{label}</div>
+      )}
+      <div className="relative">
+        <Input
+          value={value}
+          type={showValue ? "text" : "password"}
+          placeholder={
+            hasStoredValue ? "已配置，留空则保持不变" : placeholder
+          }
+          autoComplete="new-password"
+          onChange={(event) => {
+            const nextValue = event.target.value;
+            if (!nextValue) setShowValue(false);
+            onChange(nextValue);
+          }}
+          className="border-hairline-strong bg-background pr-10 text-foreground placeholder:text-muted-soft"
+        />
+        <button
+          type="button"
+          disabled={!value}
+          onClick={() => setShowValue((current) => !current)}
+          className="absolute right-3 top-1/2 -translate-y-1/2 text-muted-soft transition-colors hover:text-foreground disabled:cursor-not-allowed disabled:opacity-40"
+          aria-label={showValue ? "隐藏 API Key" : "显示 API Key"}
+        >
+          {showValue ? <EyeOff size={16} /> : <Eye size={16} />}
+        </button>
+      </div>
+      {hasStoredValue && (
+        <p className="mt-2 text-xs leading-5 text-muted-foreground">
+          已有密钥不会返回浏览器。留空可保持原密钥，输入新值将覆盖原密钥。
+        </p>
+      )}
+    </label>
+  );
+}
+
 function TextAreaField({
   label,
   value,
diff --git a/frontend/src/components/pages/ComponentsModelsPage.tsx b/frontend/src/components/pages/ComponentsModelsPage.tsx
index 3bc793e..4ca1480 100644
--- a/frontend/src/components/pages/ComponentsModelsPage.tsx
+++ b/frontend/src/components/pages/ComponentsModelsPage.tsx
@@ -145,7 +145,9 @@ export function ComponentsModelsPage() {
     try {
       // TODO: 接入真实疎通接口（按 form.interfaceType 区分调用方式）
       await new Promise((resolve) => setTimeout(resolve, 900));
-      const reachable = Boolean(form.apiUrl.trim() && form.apiKey.trim());
+      const reachable = Boolean(
+        form.apiUrl.trim() && (form.apiKey.trim() || editingModel?.apiKey),
+      );
       setTestResult(reachable ? "ok" : "fail");
     } catch {
       setTestResult("fail");
@@ -186,8 +188,8 @@ export function ComponentsModelsPage() {
       type: model.type,
       interfaceType: model.interfaceType,
       apiUrl: model.apiUrl,
-      // 后端回传已打码,原样带回 → 不修改则保留旧 key(写时哨兵)
-      apiKey: model.apiKey,
+      // 编辑时不把打码占位符放入输入框；空值写回后端表示保留旧 key
+      apiKey: "",
     });
     setShowKey(false);
     setTestResult("idle");
@@ -282,6 +284,7 @@ export function ComponentsModelsPage() {
   }
 
   const interfaceOptions = interfaceOptionsByType[form.type];
+  const hasStoredApiKey = Boolean(editingId && editingModel?.apiKey);
   const canSave =
     form.name.trim() && form.modelId.trim() && form.apiUrl.trim();
 
@@ -699,18 +702,29 @@ export function ComponentsModelsPage() {
                   value={form.apiKey}
                   type={showKey ? "text" : "password"}
                   onChange={(event) => updateForm("apiKey", event.target.value)}
-                  placeholder="请输入 API Key"
+                  placeholder={
+                    hasStoredApiKey
+                      ? "已配置，留空则保持不变"
+                      : "请输入 API Key"
+                  }
+                  autoComplete="new-password"
                   className="border-hairline-strong bg-background pr-10 text-foreground placeholder:text-muted-soft"
                 />
                 <button
                   type="button"
                   onClick={() => setShowKey((value) => !value)}
-                  className="absolute right-3 top-1/2 -translate-y-1/2 text-muted-soft transition-colors hover:text-foreground"
+                  disabled={!form.apiKey}
+                  className="absolute right-3 top-1/2 -translate-y-1/2 text-muted-soft transition-colors hover:text-foreground disabled:cursor-not-allowed disabled:opacity-40"
                   aria-label={showKey ? "隐藏 API Key" : "显示 API Key"}
                 >
                   {showKey ? <EyeOff size={16} /> : <Eye size={16} />}
                 </button>
               </div>
+              {hasStoredApiKey && (
+                <p className="mt-2 text-xs leading-5 text-muted-foreground">
+                  已有密钥不会返回浏览器。留空可保持原密钥，输入新值将覆盖原密钥。
+                </p>
+              )}
             </div>
           </div>