diff --git a/web/src/features/auth/RegisterPage.tsx b/web/src/features/auth/RegisterPage.tsx
index 60d357c1..7888ea45 100644
--- a/web/src/features/auth/RegisterPage.tsx
+++ b/web/src/features/auth/RegisterPage.tsx
@@ -1,4 +1,4 @@
-import { useRef, useState } from 'react';
+import { useEffect, useRef, useState } from 'react';
 
 import { Link, Navigate, useNavigate } from 'react-router-dom';
 
@@ -33,9 +33,18 @@ export function RegisterPage() {
   const [agreed, setAgreed] = useState(false);
   const [submitting, setSubmitting] = useState(false);
   const [error, setError] = useState('');
+  const [legalDocument, setLegalDocument] = useState<'terms' | 'privacy' | null>(null);
+  const legalDialogRef = useRef<HTMLDialogElement>(null);
   const verifiedRef = useRef<{ key: string; response: string } | null>(null);
   const submitRef = useRef(false);
 
+  useEffect(() => {
+    const dialog = legalDialogRef.current;
+    if (!dialog) return;
+    if (legalDocument && !dialog.open) dialog.showModal();
+    if (!legalDocument && dialog.open) dialog.close();
+  }, [legalDocument]);
+
   if (!tenant) return <Navigate to="/tenant" replace />;
   const minPasswordLength = tenant.passwordPolicy?.minLength ?? 8;
   // The deployed file endpoint is pinned to the IM API host; the web host serves
@@ -146,7 +155,7 @@ export function RegisterPage() {
             autoComplete="new-password" maxLength={tenant.passwordPolicy?.maxLength} />
           <label className="flex items-start gap-2 text-sm text-text-secondary">
             <input type="checkbox" checked={agreed} onChange={(e) => setAgreed(e.target.checked)} className="mt-1" />
-            <span>我已阅读并同意 <a href={`${legalOrigin}/legal/user-terms`} target="_blank" rel="noreferrer" className="text-accent">用户条款</a> 和 <a href={`${legalOrigin}/legal/privacy-policy`} target="_blank" rel="noreferrer" className="text-accent">隐私政策</a></span>
+            <span>我已阅读并同意 <button type="button" onClick={() => setLegalDocument('terms')} className="cursor-pointer p-0 text-accent">用户条款</button> 和 <button type="button" onClick={() => setLegalDocument('privacy')} className="cursor-pointer p-0 text-accent">隐私政策</button></span>
           </label>
           <button type="submit" disabled={submitting || !agreed || (!username && !phone)}
             className="h-[50px] rounded-md bg-btn text-base font-medium text-white disabled:bg-btn-disabled">
@@ -154,6 +163,29 @@ export function RegisterPage() {
           </button>
         </form>
       </main>
+      <dialog
+        ref={legalDialogRef}
+        onClose={() => setLegalDocument(null)}
+        className="m-auto h-[min(88dvh,800px)] w-[min(92vw,800px)] overflow-hidden rounded-md border border-border-panel bg-white p-0 shadow-xl backdrop:bg-black/50"
+        aria-label={legalDocument === 'privacy' ? '隐私政策' : '用户条款'}
+      >
+        <div className="flex h-full min-h-0 flex-col">
+          <div className="flex h-14 shrink-0 items-center justify-between border-b border-border-panel px-5">
+            <h2 className="m-0 text-base font-semibold text-text-title">{legalDocument === 'privacy' ? '隐私政策' : '用户条款'}</h2>
+            <button type="button" onClick={() => legalDialogRef.current?.close()} aria-label="关闭协议弹窗" title="关闭"
+              className="grid h-9 w-9 place-items-center text-text-secondary hover:text-text-title">
+              <Icon name="close" className="text-[20px]" />
+            </button>
+          </div>
+          {legalDocument && <iframe
+            key={legalDocument}
+            title={legalDocument === 'privacy' ? '隐私政策正文' : '用户条款正文'}
+            src={`${legalOrigin}/legal/${legalDocument === 'privacy' ? 'privacy-policy' : 'user-terms'}`}
+            referrerPolicy="no-referrer"
+            className="min-h-0 w-full flex-1 border-0 bg-white"
+          />}
+        </div>
+      </dialog>
     </div>
   );
 }