diff --git a/eng/SourceBuild.props b/eng/SourceBuild.props
index 0bc1c2b8324..2bd3712f6ee 100644
--- a/eng/SourceBuild.props
+++ b/eng/SourceBuild.props
@@ -3,6 +3,7 @@
   <PropertyGroup>
     <GitHubRepositoryName>msbuild</GitHubRepositoryName>
     <SourceBuildManagedOnly>true</SourceBuildManagedOnly>
+    <SourceBuildTrimNetFrameworkTargets>true</SourceBuildTrimNetFrameworkTargets>
   </PropertyGroup>
 
   <Target Name="ConfigureInnerBuildArgs" BeforeTargets="GetSourceBuildCommandConfiguration">