diff --git a/protoc-gen-swagger/genswagger/template.go b/protoc-gen-swagger/genswagger/template.go
index c4f2b8d81aa..1e90ff2ddb0 100644
--- a/protoc-gen-swagger/genswagger/template.go
+++ b/protoc-gen-swagger/genswagger/template.go
@@ -611,10 +611,10 @@ func renderServices(services []*descriptor.Service, paths swaggerPathsObject, re
 					},
 				}
 				if bIdx == 0 {
-					operationObject.OperationID = fmt.Sprintf("%s", meth.GetName())
+					operationObject.OperationID = fmt.Sprintf("%s%s", svc.GetName(), meth.GetName())
 				} else {
 					// OperationID must be unique in an OpenAPI v2 definition.
-					operationObject.OperationID = fmt.Sprintf("%s%d", meth.GetName(), bIdx+1)
+					operationObject.OperationID = fmt.Sprintf("%s%s%d", svc.GetName(), meth.GetName(), bIdx+1)
 				}
 
 				// Fill reference map with referenced request messages