diff --git a/csharp/csharp.csproj b/csharp/csharp.csproj
index c5899d0..5449be0 100644
--- a/csharp/csharp.csproj
+++ b/csharp/csharp.csproj
@@ -7,7 +7,7 @@
 
   <ItemGroup>
     <PackageReference Include="Google.Api.CommonProtos" Version="1.7.0" />
-    <PackageReference Include="Google.Protobuf" Version="3.11.2" />
+    <PackageReference Include="Google.Protobuf" Version="3.15.0" />
     <PackageReference Include="Grpc" Version="2.25.0" />
     <PackageReference Include="Grpc.Tools" Version="2.25.0">
       <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>