diff --git a/src/Compilers/CSharp/Test/Symbol/Microsoft.CodeAnalysis.CSharp.Symbol.UnitTests.csproj b/src/Compilers/CSharp/Test/Symbol/Microsoft.CodeAnalysis.CSharp.Symbol.UnitTests.csproj
index 1b67339b25d2e557c50e3343a0898fe259105b4e..0e56d474bf70e1a7311965ec1062faa5044e3f30 100644
--- a/src/Compilers/CSharp/Test/Symbol/Microsoft.CodeAnalysis.CSharp.Symbol.UnitTests.csproj
+++ b/src/Compilers/CSharp/Test/Symbol/Microsoft.CodeAnalysis.CSharp.Symbol.UnitTests.csproj
@@ -9,6 +9,11 @@
     <RoslynProjectType>UnitTestPortable</RoslynProjectType>
     <RuntimeIdentifiers>$(RoslynPortableRuntimeIdentifiers)</RuntimeIdentifiers>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <!-- 
+      Mono serialization errors breaking tests that have traits
+      https://github.com/mono/mono/issues/10945
+    -->
+    <SkipTests Condition="'$(TestRuntime)' == 'Mono'">true</SkipTests>
   </PropertyGroup>
   <ItemGroup Label="Project References">
     <ProjectReference Include="..\..\..\..\Test\Utilities\Portable\Roslyn.Test.Utilities.csproj" />