diff --git a/tools/Google.Cloud.Tools.SourceManipulation/Google.Cloud.Tools.SourceManipulation.csproj b/tools/Google.Cloud.Tools.SourceManipulation/Google.Cloud.Tools.SourceManipulation.csproj
index af16db617936..155ee892386d 100644
--- a/tools/Google.Cloud.Tools.SourceManipulation/Google.Cloud.Tools.SourceManipulation.csproj
+++ b/tools/Google.Cloud.Tools.SourceManipulation/Google.Cloud.Tools.SourceManipulation.csproj
@@ -10,7 +10,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.5.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.6.0" />
   </ItemGroup>
 
   <ItemGroup>