With the development of maritime transport, maritime accidents become more frequent.Thus salvage operations become the focus of much research.Given the harsh underwater conditions, fewer traditional submarine facilities could accomplish the salvage operation well enough.However, the Autonomous Underwater Vehicle (AUV) can automatically navigate itself to find targets, which apparently let it become a powerful tool for various underwater salvage tasks.This paper presented the definition, classification and development status of Unmanned Underwater Vehicles (UUV) in recent years,it also presented the definition and example of cases about UUV salvage, from which we drew a conclusion that UUV could replace human effort to become a major tool on salvage in the future.