diff --git a/rpc/grpc/util.go b/rpc/grpc/util.go
index 61d9abb..150d57d 100644
--- a/rpc/grpc/util.go
+++ b/rpc/grpc/util.go
@@ -6,7 +6,7 @@ import (
 	"github.com/nspcc-dev/neofs-api-go/rpc/common"
 )
 
-const methodNameFmt = "%s/%s"
+const methodNameFmt = "/%s/%s"
 
 func toMethodName(p common.CallMethodInfo) string {
 	return fmt.Sprintf(methodNameFmt, p.Service, p.Name)