diff --git a/Shadowsocks.Protobuf/Shadowsocks.Protobuf.csproj b/Shadowsocks.Protobuf/Shadowsocks.Protobuf.csproj
index d122c37c..608dbf0c 100644
--- a/Shadowsocks.Protobuf/Shadowsocks.Protobuf.csproj
+++ b/Shadowsocks.Protobuf/Shadowsocks.Protobuf.csproj
@@ -5,7 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Google.Protobuf" Version="3.15.5" />
+    <PackageReference Include="Google.Protobuf" Version="3.15.6" />
   </ItemGroup>
 
 </Project>