Gravity assisted underwater inertial navigation has been a hot and cutting-edge issue in the research of underwater vehicle navigation and positioning in recent years, which is expected to become an important direction for the development of the next generation of high-precision underwater navigation systems. Firstly, the importance of underwater gravity information for correcting inertial navigation system error is introduced, and the basic principles and technical connotations of underwater gravity assisted inertial navigation are elaborated. Then, the research status and development trend of underwater gravity assisted navigation based on traditional relative gravimeter are summarized from different development stages such as unmapped matching and mapped matching. Furthermore, the demand of high-precision absolute gravimetry technology for next-generation underwater autonomous navigation system is analyzed, and the latest development and application status of atomic interferometric gravity measurement technology are reviewed and discussed. The application prospects of atomic interference gravity measurement technology in the field of underwater inertial navigation are forecasted and the key technologies that still need to be solved are summarized. Finally, the shortcomings and development suggestions of gravity assisted navigation research in China are given.