The Peer-to-Pee (P2P) applications have become quite popular in the terrestrial domain mainly due to its strong capability of sharing distributed files. However, in the marine environment, where the ship is almost isolated from the world, the p2p file sharing system could be more demanding, but not available so far. By virtues of the rapid development of the wireless telecommunications, especially the INMARSAT Fleet satellite communications, along with the provided Mobile Packet Data Service (MPDS), we propose a Mobile P2P (MP2P) architecture, which could be further utilized to implement a MP2P file-sharing system at sea. To achieve this goal, in this paper, we firstly proposed an architecture concept for Next Generation Maritime Communication Network (NGMCN). Then, on this basis, we design our layered MP2P file-sharing architecture. Finally, we use simulations to evaluate the performance of the proposed architecture and applicability to the marine environment.