diff --git a/runtime/CSharp/Antlr4.Runtime.Test/Antlr4.Runtime.Test.v4.0.csproj b/runtime/CSharp/Antlr4.Runtime.Test/Antlr4.Runtime.Test.v4.0.csproj
index 5e38cd025..51e712dae 100644
--- a/runtime/CSharp/Antlr4.Runtime.Test/Antlr4.Runtime.Test.v4.0.csproj
+++ b/runtime/CSharp/Antlr4.Runtime.Test/Antlr4.Runtime.Test.v4.0.csproj
@@ -8,7 +8,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Antlr4.Runtime.Test</RootNamespace>
     <AssemblyName>Antlr4.Runtime.Test</AssemblyName>
-    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <ProjectTypeGuids>{3AC096D0-A1C2-E12C-1390-A8335801FDAB};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
     <VisualStudioVersion Condition="'$(VisualStudioVersion)' == ''">10.0</VisualStudioVersion>
diff --git a/runtime/CSharp/Antlr4.Runtime/Antlr4.Runtime.v4.0.csproj b/runtime/CSharp/Antlr4.Runtime/Antlr4.Runtime.v4.0.csproj
index b0877576c..e382d9bb4 100644
--- a/runtime/CSharp/Antlr4.Runtime/Antlr4.Runtime.v4.0.csproj
+++ b/runtime/CSharp/Antlr4.Runtime/Antlr4.Runtime.v4.0.csproj
@@ -9,7 +9,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Antlr4.Runtime</RootNamespace>
     <AssemblyName>Antlr4.Runtime</AssemblyName>
-    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <BaseIntermediateOutputPath>obj\v4.0\</BaseIntermediateOutputPath>
   </PropertyGroup>