This paper analyzes the previous study of applying P2P technology in mobile Internet. It first introduces the P2P technology and the conception of mobile Internet, and presents the challenges and service pattern of P2P technology in mobile Internet. Second, the architectures of P2P technology in mobile Internet are described in terms of centralized architecture, super node architecture and ad hoc architecture, respectively. Further more, the resource location algorisms and cross-layer optimizations are introduced based on two different terminal access patterns. Detailed analyses of different key technologies are presented and the disadvantages are pointed out. At last, this paper outlines future research directions.