diff --git a/src/libraries/tests.proj b/src/libraries/tests.proj
index d369aba08d76ed..65f8fdf5cb1cd0 100644
--- a/src/libraries/tests.proj
+++ b/src/libraries/tests.proj
@@ -28,7 +28,6 @@
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)Microsoft.VisualBasic.Core\tests\Microsoft.VisualBasic.Core.Tests.csproj" />
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.CodeDom\tests\System.CodeDom.Tests.csproj" />
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.Collections.NonGeneric\tests\System.Collections.NonGeneric.Tests.csproj" />
-    <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.Collections.Specialized\tests\System.Collections.Specialized.Tests.csproj" />
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.ComponentModel.Annotations\tests\System.ComponentModel.Annotations.Tests.csproj" />
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.ComponentModel.Primitives\tests\System.ComponentModel.Primitives.Tests.csproj" />
     <ProjectExclusions Include="$(MSBuildThisFileDirectory)System.ComponentModel.TypeConverter\tests\System.ComponentModel.TypeConverter.Tests.csproj" />