diff --git a/crates/core/src/app.rs b/crates/core/src/app.rs
index fa2e853..9f2263c 100644
--- a/crates/core/src/app.rs
+++ b/crates/core/src/app.rs
@@ -65,6 +65,7 @@ impl CoreApp {
             ("api_port", "1234".to_string()),
             ("api_key", String::new()),
             ("api_enabled", "false".to_string()),
+            ("upload_max_mb", "10".to_string()),
         ];
         for (key, value) in defaults {
             let _ = settings::set(&db, key, &value);
diff --git a/ui/src/pages/ChatPage.tsx b/ui/src/pages/ChatPage.tsx
index db7aed2..e2e4d1b 100644
--- a/ui/src/pages/ChatPage.tsx
+++ b/ui/src/pages/ChatPage.tsx
@@ -50,9 +50,6 @@ const TEXT_EXTENSIONS = new Set([
   "yml", "toml", "ini", "sh", "ps1", "bat", "sql", "env", "gitignore",
 ]);
 
-const MAX_IMAGE_SIZE = 3 * 1024 * 1024;
-const MAX_TEXT_SIZE = 100 * 1024;
-
 export default function ChatPage() {
   const models = useStore((s) => s.models);
   const conversations = useStore((s) => s.conversations);
@@ -75,6 +72,7 @@ export default function ChatPage() {
   const [editingDraft, setEditingDraft] = useState("");
   const [versionsFor, setVersionsFor] = useState<Record<string, MessageVersion[]>>({});
   const [attachments, setAttachments] = useState<Attachment[]>([]);
+  const [uploadLimitMb, setUploadLimitMb] = useState(10);
   const bottomRef = useRef<HTMLDivElement>(null);
   const fileInputRef = useRef<HTMLInputElement>(null);
 
@@ -104,6 +102,13 @@ export default function ChatPage() {
     }
   }, [models, selectedModelId]);
 
+  useEffect(() => {
+    api.settingsGet().then((s) => {
+      const v = Number(s.upload_max_mb);
+      if (v > 0) setUploadLimitMb(v);
+    });
+  }, []);
+
   useEffect(() => {
     bottomRef.current?.scrollIntoView({ behavior: "smooth" });
   }, [messages]);
@@ -302,11 +307,12 @@ export default function ChatPage() {
   }
 
   async function handleFiles(files: FileList | File[]) {
+    const maxBytes = uploadLimitMb * 1024 * 1024;
     for (const file of Array.from(files)) {
       const ext = file.name.split(".").pop()?.toLowerCase() ?? "";
       if (file.type.startsWith("image/") || ["png", "jpg", "jpeg", "webp", "gif", "bmp"].includes(ext)) {
-        if (file.size > MAX_IMAGE_SIZE) {
-          setError(`图片 ${file.name} 超过 3MB，已跳过`);
+        if (file.size > maxBytes) {
+          setError(`图片 ${file.name} 超过上限 ${uploadLimitMb}MB，已跳过`);
           continue;
         }
         const dataUrl = await readAsDataUrl(file);
@@ -315,8 +321,8 @@ export default function ChatPage() {
           { id: crypto.randomUUID(), kind: "image", name: file.name, size: file.size, dataUrl },
         ]);
       } else if (file.type.startsWith("text/") || TEXT_EXTENSIONS.has(ext)) {
-        if (file.size > MAX_TEXT_SIZE) {
-          setError(`文件 ${file.name} 超过 100KB，已跳过`);
+        if (file.size > maxBytes) {
+          setError(`文件 ${file.name} 超过上限 ${uploadLimitMb}MB，已跳过`);
           continue;
         }
         const text = await file.text();
@@ -468,7 +474,7 @@ export default function ChatPage() {
             <button
               className="mb-1 flex h-9 w-9 shrink-0 items-center justify-center rounded-lg border border-border bg-panel-2 text-slate-400 hover:bg-panel-2/60 hover:text-slate-200"
               onClick={() => fileInputRef.current?.click()}
-              title="上传图片或文本文件"
+              title={`上传图片或文本文件（上限 ${uploadLimitMb}MB）`}
             >
               <Icon name="paperclip" className="h-4 w-4" />
             </button>
diff --git a/ui/src/pages/SettingsPage.tsx b/ui/src/pages/SettingsPage.tsx
index fe466fc..9e5c1bd 100644
--- a/ui/src/pages/SettingsPage.tsx
+++ b/ui/src/pages/SettingsPage.tsx
@@ -77,6 +77,11 @@ export default function SettingsPage() {
               value={settings.backend ?? ""}
               onSave={(v) => handleSave("backend", v)}
             />
+            <SettingInput
+              label="上传图片/文件大小上限（MB）"
+              value={settings.upload_max_mb ?? "10"}
+              onSave={(v) => handleSave("upload_max_mb", v)}
+            />
           </div>
         </div>