diff --git a/web/app/components/workflow/comment/thread.tsx b/web/app/components/workflow/comment/thread.tsx
index ec098deb69..48417550cd 100644
--- a/web/app/components/workflow/comment/thread.tsx
+++ b/web/app/components/workflow/comment/thread.tsx
@@ -1,10 +1,13 @@
 'use client'
 
+import { useParams } from 'next/navigation'
 import type { FC } from 'react'
 import { memo, useCallback, useEffect, useMemo, useState } from 'react'
 import { useReactFlow, useViewport } from 'reactflow'
-import { RiArrowDownSLine, RiArrowUpSLine, RiCheckboxCircleFill, RiCheckboxCircleLine, RiCloseLine, RiDeleteBinLine } from '@remixicon/react'
+import { RiArrowDownSLine, RiArrowUpSLine, RiCheckboxCircleFill, RiCheckboxCircleLine, RiCloseLine, RiDeleteBinLine, RiMoreFill } from '@remixicon/react'
+import Textarea from 'react-textarea-autosize'
 import Avatar from '@/app/components/base/avatar'
+import Button from '@/app/components/base/button'
 import Divider from '@/app/components/base/divider'
 import cn from '@/utils/classnames'
 import { useFormatTimeFromNow } from '@/app/components/workflow/hooks'
@@ -23,6 +26,8 @@ type CommentThreadProps = {
   canGoPrev?: boolean
   canGoNext?: boolean
   onReply?: (content: string, mentionedUserIds?: string[]) => Promise<void> | void
+  onReplyEdit?: (replyId: string, content: string, mentionedUserIds?: string[]) => Promise<void> | void
+  onReplyDelete?: (replyId: string) => void
 }
 
 const ThreadMessage: FC<{
@@ -56,16 +61,6 @@ const ThreadMessage: FC<{
   )
 }
 
-const renderReply = (reply: WorkflowCommentDetailReply) => (
-  <ThreadMessage
-    key={reply.id}
-    authorName={reply.created_by_account?.name || 'User'}
-    avatarUrl={reply.created_by_account?.avatar_url || null}
-    createdAt={reply.created_at}
-    content={reply.content}
-  />
-)
-
 export const CommentThread: FC<CommentThreadProps> = memo(({
   comment,
   loading = false,
@@ -77,11 +72,16 @@ export const CommentThread: FC<CommentThreadProps> = memo(({
   canGoPrev,
   canGoNext,
   onReply,
+  onReplyEdit,
+  onReplyDelete,
 }) => {
+  const params = useParams()
   const { flowToScreenPosition } = useReactFlow()
   const viewport = useViewport()
   const { userProfile } = useAppContext()
   const [replyContent, setReplyContent] = useState('')
+  const [activeReplyMenuId, setActiveReplyMenuId] = useState<string | null>(null)
+  const [editingReply, setEditingReply] = useState<{ id: string; content: string }>({ id: '', content: '' })
 
   useEffect(() => {
     setReplyContent('')
@@ -106,6 +106,25 @@ export const CommentThread: FC<CommentThreadProps> = memo(({
     })
   }, [comment.position_x, comment.position_y, viewport.x, viewport.y, viewport.zoom, flowToScreenPosition])
 
+  const handleStartEdit = useCallback((reply: WorkflowCommentDetailReply) => {
+    setEditingReply({ id: reply.id, content: reply.content })
+    setActiveReplyMenuId(null)
+  }, [])
+
+  const handleCancelEdit = useCallback(() => {
+    setEditingReply({ id: '', content: '' })
+  }, [])
+
+  const handleSaveEdit = useCallback(async () => {
+    if (!onReplyEdit || !editingReply) return
+    const trimmed = editingReply.content.trim()
+    if (!trimmed) return
+    await onReplyEdit(editingReply.id, trimmed, [])
+    setEditingReply({ id: '', content: '' })
+  }, [editingReply, onReplyEdit])
+
+  const replies = comment.replies || []
+
   return (
     <div
       className='absolute z-50 w-[360px] max-w-[360px]'
@@ -173,9 +192,72 @@ export const CommentThread: FC<CommentThreadProps> = memo(({
             createdAt={comment.created_at}
             content={comment.content}
           />
-          {comment.replies?.length > 0 && (
-            <div className='mt-3 space-y-3 pt-3'>
-              {comment.replies.map(renderReply)}
+          {replies.length > 0 && (
+            <div className='mt-2 space-y-3 pt-3'>
+              {replies.map((reply) => {
+                const isReplyEditing = editingReply?.id === reply.id
+                return (
+                  <div
+                    key={reply.id}
+                    className='group relative rounded-lg py-2 transition-colors hover:bg-components-panel-on-panel-item-bg'
+                  >
+                    <div className='absolute right-1 top-1 hidden gap-1 group-hover:flex'>
+                      <button
+                        type='button'
+                        className='flex h-6 w-6 items-center justify-center rounded-md text-text-tertiary hover:bg-state-base-hover hover:text-text-secondary'
+                        onClick={(e) => {
+                          e.stopPropagation()
+                          setActiveReplyMenuId(prev => prev === reply.id ? null : reply.id)
+                        }}
+                        aria-label='Reply actions'
+                      >
+                        <RiMoreFill className='h-4 w-4' />
+                      </button>
+                      {activeReplyMenuId === reply.id && (
+                        <div className='absolute right-0 top-7 z-40 w-36 rounded-lg border border-components-panel-border bg-components-panel-bg shadow-lg'>
+                          <button
+                            className='flex w-full items-center justify-start px-3 py-2 text-left text-sm text-text-secondary hover:bg-state-base-hover'
+                            onClick={() => handleStartEdit(reply)}
+                          >
+                            Edit reply
+                          </button>
+                          <button
+                            className='text-negative flex w-full items-center justify-start px-3 py-2 text-left text-sm hover:bg-state-base-hover'
+                            onClick={() => {
+                              setActiveReplyMenuId(null)
+                              onReplyDelete?.(reply.id)
+                            }}
+                          >
+                            Delete reply
+                          </button>
+                        </div>
+                      )}
+                    </div>
+                    {isReplyEditing ? (
+                      <div className='rounded-lg border border-components-chat-input-border bg-components-panel-bg-blur px-3 py-2 shadow-sm'>
+                        <Textarea
+                          minRows={1}
+                          maxRows={4}
+                          value={editingReply?.content ?? ''}
+                          onChange={e => setEditingReply(prev => prev ? { ...prev, content: e.target.value } : prev)}
+                          className='system-sm-regular w-full resize-none bg-transparent text-text-primary caret-primary-500 outline-none'
+                        />
+                        <div className='mt-2 flex items-center justify-end gap-2'>
+                          <Button variant='secondary' size='small' onClick={handleCancelEdit} disabled={loading}>Cancel</Button>
+                          <Button variant='primary' size='small' disabled={loading || !(editingReply?.content?.trim())} onClick={handleSaveEdit}>Save</Button>
+                        </div>
+                      </div>
+                    ) : (
+                      <ThreadMessage
+                        authorName={reply.created_by_account?.name || 'User'}
+                        avatarUrl={reply.created_by_account?.avatar_url || null}
+                        createdAt={reply.created_at}
+                        content={reply.content}
+                      />
+                    )}
+                  </div>
+                )
+              })}
             </div>
           )}
         </div>
diff --git a/web/app/components/workflow/hooks/use-workflow-comment.ts b/web/app/components/workflow/hooks/use-workflow-comment.ts
index e0048d2b95..7e1cc4cdd1 100644
--- a/web/app/components/workflow/hooks/use-workflow-comment.ts
+++ b/web/app/components/workflow/hooks/use-workflow-comment.ts
@@ -4,7 +4,7 @@ import { useReactFlow } from 'reactflow'
 import { useStore } from '../store'
 import { ControlMode } from '../types'
 import type { WorkflowCommentDetail, WorkflowCommentList } from '@/service/workflow-comment'
-import { createWorkflowComment, createWorkflowCommentReply, deleteWorkflowComment, fetchWorkflowComment, fetchWorkflowComments, resolveWorkflowComment } from '@/service/workflow-comment'
+import { createWorkflowComment, createWorkflowCommentReply, deleteWorkflowComment, deleteWorkflowCommentReply, fetchWorkflowComment, fetchWorkflowComments, resolveWorkflowComment, updateWorkflowCommentReply } from '@/service/workflow-comment'
 
 export const useWorkflowComment = () => {
   const params = useParams()
@@ -217,6 +217,42 @@ export const useWorkflowComment = () => {
     }
   }, [appId, loadComments, refreshActiveComment, setActiveCommentLoading])
 
+  const handleCommentReplyUpdate = useCallback(async (commentId: string, replyId: string, content: string, mentionedUserIds: string[] = []) => {
+    if (!appId) return
+    const trimmed = content.trim()
+    if (!trimmed) return
+
+    setActiveCommentLoading(true)
+    try {
+      await updateWorkflowCommentReply(appId, commentId, replyId, { content: trimmed, mentioned_user_ids: mentionedUserIds })
+      await refreshActiveComment(commentId)
+      await loadComments()
+    }
+    catch (error) {
+      console.error('Failed to update reply:', error)
+    }
+    finally {
+      setActiveCommentLoading(false)
+    }
+  }, [appId, loadComments, refreshActiveComment, setActiveCommentLoading])
+
+  const handleCommentReplyDelete = useCallback(async (commentId: string, replyId: string) => {
+    if (!appId) return
+
+    setActiveCommentLoading(true)
+    try {
+      await deleteWorkflowCommentReply(appId, commentId, replyId)
+      await refreshActiveComment(commentId)
+      await loadComments()
+    }
+    catch (error) {
+      console.error('Failed to delete reply:', error)
+    }
+    finally {
+      setActiveCommentLoading(false)
+    }
+  }, [appId, loadComments, refreshActiveComment, setActiveCommentLoading])
+
   const handleCommentNavigate = useCallback((direction: 'prev' | 'next') => {
     const currentId = activeCommentIdRef.current
     if (!currentId) return
@@ -261,6 +297,9 @@ export const useWorkflowComment = () => {
     handleCommentDelete,
     handleCommentNavigate,
     handleCommentReply,
+    handleCommentReplyUpdate,
+    handleCommentReplyDelete,
+    refreshActiveComment,
     handleCreateComment,
     loadComments,
   }
diff --git a/web/app/components/workflow/index.tsx b/web/app/components/workflow/index.tsx
index ec3da2c794..a21d5094f4 100644
--- a/web/app/components/workflow/index.tsx
+++ b/web/app/components/workflow/index.tsx
@@ -118,6 +118,7 @@ export const Workflow: FC<WorkflowProps> = memo(({
   const reactflow = useReactFlow()
   const [isMouseOverCanvas, setIsMouseOverCanvas] = useState(false)
   const [pendingDeleteCommentId, setPendingDeleteCommentId] = useState<string | null>(null)
+  const [pendingDeleteReply, setPendingDeleteReply] = useState<{ commentId: string; replyId: string } | null>(null)
   const [nodes, setNodes] = useNodesState(originalNodes)
   const [edges, setEdges] = useEdgesState(originalEdges)
   const controlMode = useStore(s => s.controlMode)
@@ -175,6 +176,8 @@ export const Workflow: FC<WorkflowProps> = memo(({
     handleCommentDelete,
     handleCommentNavigate,
     handleCommentReply,
+    handleCommentReplyUpdate,
+    handleCommentReplyDelete,
   } = useWorkflowComment()
   const mousePosition = useStore(s => s.mousePosition)
 
@@ -358,6 +361,18 @@ export const Workflow: FC<WorkflowProps> = memo(({
           }}
         />
       )}
+      {pendingDeleteReply && (
+        <Confirm
+          isShow
+          title='Delete this reply?'
+          content='This reply will be removed permanently.'
+          onCancel={() => setPendingDeleteReply(null)}
+          onConfirm={async () => {
+            await handleCommentReplyDelete(pendingDeleteReply.commentId, pendingDeleteReply.replyId)
+            setPendingDeleteReply(null)
+          }}
+        />
+      )}
       <LimitTips />
       {controlMode === ControlMode.Comment && isMouseOverCanvas && (
         <CommentCursor mousePosition={mousePosition} />
@@ -386,6 +401,8 @@ export const Workflow: FC<WorkflowProps> = memo(({
               onPrev={canGoPrev ? () => handleCommentNavigate('prev') : undefined}
               onNext={canGoNext ? () => handleCommentNavigate('next') : undefined}
               onReply={(content, ids) => handleCommentReply(comment.id, content, ids ?? [])}
+              onReplyEdit={(replyId, content, ids) => handleCommentReplyUpdate(comment.id, replyId, content, ids ?? [])}
+              onReplyDelete={replyId => setPendingDeleteReply({ commentId: comment.id, replyId })}
               canGoPrev={canGoPrev}
               canGoNext={canGoNext}
             />