Wireless MESH network is considered to be one of the candidates for solving the last mile problem in high speed network services. Traditional MESH network faces the challenge of scalability due to the features of self-organization and multihop connection. In this short paper we propose a hierarchical architecture for large size MESH networks. A MESH network is divided into small networks, which are operated independently and are connected through a reliable backbone network. We present the architecture and address routing/security issues.