diff --git a/src/ruby/README.md b/src/ruby/README.md
index f476fe72be2fecc1ef2c9f2438e41dd19772f109..266d6b2c1682bc9e3dd8c1f07c7a962ae118a0d6 100644
--- a/src/ruby/README.md
+++ b/src/ruby/README.md
@@ -59,7 +59,7 @@ Directory structure is the layout for [ruby extensions][]
 - bin: example gRPC clients and servers, e.g,
 
   ```ruby
-  stub = Math::Math::Stub.new('my.test.math.server.com:8080')
+  stub = Math::Math::Stub.new('my.test.math.server.com:8080', :this_channel_is_insecure)
   req = Math::DivArgs.new(dividend: 7, divisor: 3)
   GRPC.logger.info("div(7/3): req=#{req.inspect}")
   resp = stub.div(req)