In order to enhance the navigation and sensing capabilities of underwater vehicles, artificial lateral line systems were built in underwater vehicles by simulating fish lateral lines. This paper introduces the function of fish lateral line and the research status of artificial lateral line at home and abroad, analyzes the biological model of lateral tube neuromast and the principle of BP neural network algorithm. The test and numerical simulation methods are combined to collect the static pressure data of the underwater vehicle under different flow fields. The flow velocity and the flow angle of the flow field are identified by a neural network algorithm. The results show that the BP neural network algorithm can effectively identify the flow field parameters, and the recognition rate is over 95%.