diff --git a/Client/src/components/PostEditor.tsx b/Client/src/components/PostEditor.tsx
new file mode 100644
index 0000000..63f5ceb
--- /dev/null
+++ b/Client/src/components/PostEditor.tsx
@@ -0,0 +1,107 @@
+import { useState } from 'react'
+import { createPost, updatePost, type Post, type PostError } from '../api/posts'
+import { Markdown } from './Markdown'
+
+interface PostEditorProps {
+  token: string
+  post?: Post
+  onSaved: () => void
+  onCancel: () => void
+}
+
+const ERROR_TEXT: Record<PostError, string> = {
+  full: '文章数已达上限（200 篇）',
+  'too-large': '正文太长了（上限 64KB）',
+  'bad-input': '标题不能为空，标签也别太长',
+  failed: '保存失败，稍后再试',
+}
+
+export function PostEditor({ token, post, onSaved, onCancel }: PostEditorProps) {
+  const [title, setTitle] = useState(post?.title ?? '')
+  const [tag, setTag] = useState(post?.tag ?? '')
+  const [body, setBody] = useState(post?.body ?? '')
+  const [preview, setPreview] = useState(false)
+  const [saving, setSaving] = useState(false)
+  const [error, setError] = useState<string | null>(null)
+
+  const save = async () => {
+    setSaving(true)
+    setError(null)
+    try {
+      const input = { title, tag, body }
+      if (post) await updatePost(token, post.id, input)
+      else await createPost(token, input)
+      onSaved()
+    } catch (e) {
+      const reason = (e as Error).message as PostError
+      setError(ERROR_TEXT[reason] ?? ERROR_TEXT.failed)
+      setSaving(false)
+    }
+  }
+
+  return (
+    <section className="w-full px-6 py-14">
+      <div className="mb-8 flex items-center justify-between">
+        <h2 className="text-xs font-medium uppercase tracking-[0.3em] text-muted">
+          {post ? 'Edit post' : 'New post'}
+        </h2>
+        <button
+          onClick={() => setPreview((p) => !p)}
+          className="rounded-full border border-line px-4 py-1.5 text-xs font-medium uppercase tracking-[0.16em] text-muted transition-colors hover:border-accent hover:text-accent"
+        >
+          {preview ? 'Write' : 'Preview'}
+        </button>
+      </div>
+
+      {preview ? (
+        <article>
+          <h1 className="mb-6 font-display text-3xl font-medium text-text">
+            {title || '（无标题）'}
+          </h1>
+          <Markdown>{body || '_正文为空_'}</Markdown>
+        </article>
+      ) : (
+        <div className="flex flex-col gap-4">
+          <input
+            value={title}
+            onChange={(e) => setTitle(e.target.value)}
+            placeholder="标题"
+            className="w-full rounded-lg border border-line bg-surface px-4 py-3 font-display text-2xl text-text outline-none focus:border-accent"
+          />
+          <input
+            value={tag}
+            onChange={(e) => setTag(e.target.value)}
+            placeholder="标签（如 Rust、随笔）"
+            className="w-full rounded-lg border border-line bg-surface px-4 py-2 text-sm text-text outline-none focus:border-accent"
+          />
+          <textarea
+            value={body}
+            onChange={(e) => setBody(e.target.value)}
+            placeholder="正文，支持 Markdown…"
+            rows={16}
+            className="w-full resize-y rounded-lg border border-line bg-surface px-4 py-3 font-mono text-sm leading-relaxed text-text outline-none focus:border-accent"
+          />
+        </div>
+      )}
+
+      {error && <p className="mt-4 text-sm text-[#ff8585]">{error}</p>}
+
+      <div className="mt-8 flex items-center gap-3">
+        <button
+          onClick={save}
+          disabled={saving}
+          className="rounded-full bg-accent px-6 py-2 text-sm font-medium text-bg transition-opacity hover:opacity-90 disabled:opacity-50"
+        >
+          {saving ? '保存中…' : '保存'}
+        </button>
+        <button
+          onClick={onCancel}
+          disabled={saving}
+          className="rounded-full border border-line px-6 py-2 text-sm font-medium text-muted transition-colors hover:border-accent hover:text-accent disabled:opacity-50"
+        >
+          取消
+        </button>
+      </div>
+    </section>
+  )
+}