diff --git a/frontend/src/test/outbound-link-parser.test.ts b/frontend/src/test/outbound-link-parser.test.ts
index ef1fe455b..3ab512b87 100644
--- a/frontend/src/test/outbound-link-parser.test.ts
+++ b/frontend/src/test/outbound-link-parser.test.ts
@@ -250,6 +250,19 @@ describe('parseShadowsocksLink', () => {
     expect(settings.servers[0].method).toBe('aes-256-gcm');
     expect(settings.servers[0].password).toBe('legacypw');
   });
+
+  it('decodes URL-safe base64 userinfo (as the emitter writes it)', () => {
+    // genShadowsocksLink emits Base64.encode(method:password, true) — URL-safe,
+    // so a password whose encoding contains - or _ must still round-trip.
+    const method = 'aes-256-gcm';
+    const password = '>>>';
+    const userinfo = Base64.encode(`${method}:${password}`, true);
+    expect(userinfo).toMatch(/[-_]/);
+    const out = parseShadowsocksLink(`ss://${userinfo}@1.2.3.4:8388#urlsafe`);
+    const settings = out?.settings as { servers: Array<{ method: string; password: string }> };
+    expect(settings.servers[0].method).toBe(method);
+    expect(settings.servers[0].password).toBe(password);
+  });
 });
 
 describe('parseHysteria2Link', () => {
diff --git a/frontend/src/utils/index.ts b/frontend/src/utils/index.ts
index c58ce781c..845c3e109 100644
--- a/frontend/src/utils/index.ts
+++ b/frontend/src/utils/index.ts
@@ -641,8 +641,10 @@ export class Base64 {
   }
 
   static decode(content: string = ''): string {
+    const normalized = content.replace(/-/g, '+').replace(/_/g, '/');
+    const padded = normalized.padEnd(Math.ceil(normalized.length / 4) * 4, '=');
     return new TextDecoder().decode(
-      Uint8Array.from(window.atob(content), (c) => c.charCodeAt(0)),
+      Uint8Array.from(window.atob(padded), (c) => c.charCodeAt(0)),
     );
   }
 }