The research was carried on centered about the key technology in the Proxy Mobile Ipv6 networks. The frame based on multi-level domains multicast agent was proposed. And the multi-level domains multicast agent who can be collocated easily was also introduced. The different service area of multi-level domains multicast agent is overlapped which can avoid “single point of failure.” The router advertisements of Ipv6 discovered the dynamic change of availed multi-level domains multicast agent and network topology. An ASMM (Auto Study Mobile Multicast) program was proposed on the based frame of multi-level domains multicast agent. The way of sending multicast data in outer region can be chosen neatly taking advantage of the number of mobile host in outer region according to the network situation in this program instead of sending multicast data in only one mode which achieved seamless handover. In recent years, the rapid development of internet and mobile networks makes people demand the combination of internet and mobile networks more and more eagerly which can provide extensive business for mobile users. And multicast is a very promising technology in mobile network. It can enable a group of mobile users to receive the message from the same business source at the same time which improved network efficiency greatly . The mobile multicast technology is facing many problems. Firstly, all multicast technology was designed for fixed host; the multicast tree established on these agreements can be changed easily. And it will cost much if it is changed; Secondly, The mobile multicast technology not only considers the dynamic change of every group members but also the location dynamic change of every group members [2, 3]. So, the mobile multicast technology is a research focus at present. IETF and many researchers proposed much mobile multicast agreement. But these agreements have different inadequateness.