Abstract: A marine gravity survey by unmanned ship can effectively solve the problems of limited water depth and low efficiency of traditional manned ship survey. By testing the marine test of unmanned ship carrying strapdown gravimeter, the measured gravity data of unmanned ship under high dynamic conditions were obtained for the first time, and a set of gravity data extraction method suitable for strapdown gravimeter was proposed. The data processing and comparative analysis showed that the accuracy of gravity data could be effectively controlled, which fully proved the applicability of unmanned ship gravity measurement, and accumulates valuable experience for the subsequent development of unmanned ship gravity meter.