Providing Internet data services is recognized as an important service in the next generation wireless communication networks. To realize such mobile Internet services, host mobility has to be supported. As a basic solution to the mentioned problem, Mobile IPv6 is proposed in IETF for IPv6 networks. In this paper, we propose a multicast-based localized mobility suppport scheme in IPv6 networks. The proposed scheme utilizes a class of multicast protocol, PIMSM, and auto-configuration of multicast group addresses in the visited network. The objectives of the proposed scheme are to reduce signaling to the Internet backbone and to maximize data delivery efficiency during frequent handoffs. Through simulation, the performance of the proposed scheme is analyzed in terms of packet loss and throughput. The results show that the proposed scheme gives better performance than Mobile IPv6 and Hierarchical Mobile IPv6.