diff --git a/client/grpc/grpc.go b/client/grpc/grpc.go
index 9ed206c6d6..555fed0e93 100644
--- a/client/grpc/grpc.go
+++ b/client/grpc/grpc.go
@@ -280,7 +280,7 @@ func (g *grpcClient) Options() client.Options {
 }
 
 func (g *grpcClient) NewMessage(topic string, msg interface{}, opts ...client.MessageOption) client.Message {
-	return newGRPCPublication(topic, msg, "application/octet-stream")
+	return newGRPCPublication(topic, msg, g.opts.ContentType, opts...)
 }
 
 func (g *grpcClient) NewRequest(service, method string, req interface{}, reqOpts ...client.RequestOption) client.Request {