diff --git a/tools/dockerfile/grpc_interop_csharp/Dockerfile b/tools/dockerfile/grpc_interop_csharp/Dockerfile
index 3789cd3203842cbde3e195a6f448b4a359450ece..93cd25010efab73f6ef6ace10c92305746db0cfd 100644
--- a/tools/dockerfile/grpc_interop_csharp/Dockerfile
+++ b/tools/dockerfile/grpc_interop_csharp/Dockerfile
@@ -80,13 +80,9 @@ RUN echo "deb http://download.mono-project.com/repo/debian wheezy-libtiff-compat
 # Install dependencies
 RUN apt-get update && apt-get -y dist-upgrade && apt-get install -y \
     mono-devel \
-    nunit \
-    nunit-console \
-    monodevelop
-
-# Download NuGet
-RUN cd /var/local && wget www.nuget.org/NuGet.exe
-ENV NUGET mono /var/local/NuGet.exe
+    ca-certificates-mono \
+    nuget \
+    && apt-get clean
 
 # Define the default command.
 CMD ["bash"]
diff --git a/tools/dockerfile/grpc_interop_csharp/build_interop.sh b/tools/dockerfile/grpc_interop_csharp/build_interop.sh
index dc1f7a331ab0350388e755021d11440b166cf002..fd5436c44ff3fb96bfa9691d9b30e8c5b5ed270d 100755
--- a/tools/dockerfile/grpc_interop_csharp/build_interop.sh
+++ b/tools/dockerfile/grpc_interop_csharp/build_interop.sh
@@ -40,6 +40,4 @@ cp -r /var/local/jenkins/service_account $HOME || true
 cd /var/local/git/grpc
 
 # build C# interop client & server
-make CONFIG=dbg grpc_csharp_ext
-(cd src/csharp && mono /var/local/NuGet.exe restore Grpc.sln)
-(cd src/csharp && xbuild Grpc.sln)
+tools/run_tests/run_tests.py -l csharp -c dbg --build_only