diff --git a/Rx.NET/Source/tests/Tests.System.Reactive/Tests.System.Reactive.csproj b/Rx.NET/Source/tests/Tests.System.Reactive/Tests.System.Reactive.csproj
index 422339e5d..a6618fc45 100644
--- a/Rx.NET/Source/tests/Tests.System.Reactive/Tests.System.Reactive.csproj
+++ b/Rx.NET/Source/tests/Tests.System.Reactive/Tests.System.Reactive.csproj
@@ -29,7 +29,7 @@
     specific Windows version.
 -->
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.9.0" />
-    <PackageReference Include="MSTest.TestAdapter" Version="3.3.1" />
+    <PackageReference Include="MSTest.TestAdapter" Version="3.4.1" />
     <PackageReference Include="MSTest.TestFramework" Version="3.3.1" />
     <PackageReference Include="xunit.assert" Version="2.8.0" />
     <ProjectReference Include="..\..\src\System.Reactive\System.Reactive.csproj" />