This paper proposes a query language to consistently access metadata registries. In current, many metadata registries have been built in various fields. Unfortunately, there is no access method to access the metadata registries in a standard manner. Thus many management systems have been developed in various and different access methods to build and manage their metadata regstry. In this paper, we propose a metadata registry query language that allows us to access consistently all metadata registries in a standardized manner. The query language is an extension of the standard query language for the relational databases SQL which is familiar to existing database managers, Consequently, the proposed metadata registry query language reduces the development cost of a metadata registry management system, And it also enables all metadata registries to be accessed in a consistent manner.