The military requirements of unmanned underwater vehicles are researched for unmanned underwater submarine vehicles can provide anti-submarine barrier for surface vessels.According to the characteristics of underwater threats of surface vessels,the basic requirements of unmanned underwater vehicles force allocation are put forward.Based on the analysis of maneuver elements of both sides,submarine attack position line and the latest warning line of unmanned underwater vehicles are defined,and the expressions are derived through analytical calculation to obtain the perimeter of the latest warning line of unmanned underwater vehicles and estimate the minimum number required of unmanned underwater vehicle.According to the modeling and analytical calculation process,the affecting factors of the minimum number required of unmanned underwater vehicle are analyzed,and the sensitivity of each factor is quantitatively simulated.According to the results,6 influencing factors are divided into 4 levels.Suggestions are put forward on carrying scheme design and performance design of shipborne unmanned underwater vehicles for large surface vessels. The results show that the models and methods proposed are feasible.