diff --git a/src/components/viewer/comment/CommentArea.tsx b/src/components/viewer/comment/CommentArea.tsx
index 0f23003..a6b8b55 100644
--- a/src/components/viewer/comment/CommentArea.tsx
+++ b/src/components/viewer/comment/CommentArea.tsx
@@ -20,6 +20,8 @@ import {
   useComments,
 } from '../../../apis/comment'
 import {
+  MAX_COMMENT_LENGTH,
+  AUTHOR_MAX_COMMENT_LENGTH,
   CommentInfo,
   CommentRating,
   MainCommentInfo,
@@ -62,11 +64,10 @@ export const CommentArea = withSuspensable(function ViewerComments({
 
   const auth = useAtomValue(authAtom)
   const operation = useOperation({ id: operationId }).data
-  // FIXME: 用户名可以重名，这里会让重名用户都显示置顶按钮，需要等后端支持 operation.uploaderId 后再修复
-  const operationOwned =
-    !!operation?.uploader &&
-    !!auth.username &&
-    operation.uploader === auth.username
+
+  const operationOwned = operation && auth.userId && operation.uploaderId === auth.userId
+
+  const maxLength = operationOwned ? AUTHOR_MAX_COMMENT_LENGTH : MAX_COMMENT_LENGTH
 
   const [replyTo, setReplyTo] = useState<CommentInfo>()
 
@@ -94,7 +95,7 @@ export const CommentArea = withSuspensable(function ViewerComments({
   return (
     <CommentAreaContext.Provider value={contextValue}>
       <div>
-        <CommentForm primary className="mb-6" />
+        <CommentForm primary className="mb-6" maxLength={maxLength} />
         {comments?.map((comment) => (
           <MainComment
             key={comment.commentId}
@@ -110,8 +111,8 @@ export const CommentArea = withSuspensable(function ViewerComments({
                   sub.fromCommentId === comment.commentId
                     ? undefined
                     : find(comment.subCommentsInfos, {
-                        commentId: sub.fromCommentId,
-                      })
+                      commentId: sub.fromCommentId,
+                    })
                 }
               />
             ))}
@@ -261,6 +262,7 @@ const CommentActions = ({
   const [{ userId }] = useAtom(authAtom)
   const { operationOwned, replyTo, setReplyTo, reload } =
     useContext(CommentAreaContext)
+  const maxLength = operationOwned ? AUTHOR_MAX_COMMENT_LENGTH : MAX_COMMENT_LENGTH
 
   const [deleteDialogOpen, setDeleteDialogOpen] = useState(false)
   const [pending, setPending] = useState(false)
@@ -331,7 +333,7 @@ const CommentActions = ({
           </p>
         </Alert>
       </div>
-      {replyTo === comment && <CommentForm inputAutoFocus className="mt-4" />}
+      {replyTo === comment && <CommentForm inputAutoFocus className="mt-4" maxLength={maxLength} />}
     </div>
   )
 }
diff --git a/src/components/viewer/comment/CommentForm.tsx b/src/components/viewer/comment/CommentForm.tsx
index ce1dcdf..0ebc7e2 100644
--- a/src/components/viewer/comment/CommentForm.tsx
+++ b/src/components/viewer/comment/CommentForm.tsx
@@ -16,6 +16,7 @@ export interface CommentFormProps {
   primary?: boolean
   placeholder?: string
   inputAutoFocus?: boolean
+  maxLength?: number
 }
 
 export const CommentForm = ({
@@ -23,6 +24,7 @@ export const CommentForm = ({
   primary,
   placeholder = '发一条友善的评论吧',
   inputAutoFocus,
+  maxLength = MAX_COMMENT_LENGTH,
 }: CommentFormProps) => {
   const { operationId, replyTo, reload } = useContext(CommentAreaContext)
 
@@ -82,7 +84,7 @@ export const CommentForm = ({
         rows={2}
         growVertically
         large
-        maxLength={MAX_COMMENT_LENGTH}
+        maxLength={maxLength}
         placeholder={placeholder}
         value={message}
         onChange={(e) => setMessage(e.target.value)}
@@ -111,7 +113,7 @@ export const CommentForm = ({
         </Checkbox>
 
         <div className="ml-auto text-slate-500 text-sm">
-          {message.length}/{MAX_COMMENT_LENGTH}
+          {message.length}/{maxLength}
         </div>
       </div>
 
diff --git a/src/models/comment.ts b/src/models/comment.ts
index a6d665e..a7c726c 100644
--- a/src/models/comment.ts
+++ b/src/models/comment.ts
@@ -11,6 +11,7 @@ export const enum CommentRating {
 }
 
 export const MAX_COMMENT_LENGTH = 150
+export const AUTHOR_MAX_COMMENT_LENGTH = 500
 
 export function isMainComment(
   comment: CommentInfo,