Abstract: With the development of offshore oil and gas, the development and exploration have been expanded from shallow water to deep water in China. The deepwater site survey is an important part in the process of oil and gas exploration and development, but it has not been done in China yet.The investigation contents and technique for deepwater site are very different from the shallow water. Through summing up the experience of the shallow site survey, the investigation contents and techniques of deepwater site are studied in detail in this paper, such as underwater acoustic positioning, deep tow, ROV, AUV and geological sampling, etc. This article is designed to provide reference for the deepwater site survey.