Traditional research on the influence of acoustics environment on dipping sonar detection can hardly come to an effective conclusion of equipment usage.According to the passive sonar equation and submarine noise model, a method for computing submarine noise signal margin is established.Through its relationship with the dipping sonar detection probability, the passive detection region of dipping sonar is simulated, and the distribution law of this detection region and its influence on the submarine searching strategy are studied.On the basis of which, and in combination with such parameters as tasks, environment and equipment, research on the submarine searching strategy for dipping sonar is conducted by simulation experiment.It is concluded that:to improve the detection efficiency, the distance between the detection points of dipping sonar should make the detection space of adjacent dipping points be closed, the positive gradient dipping depth be shallow, and double-dipping depths should be used in combination.The study is of specific guiding significance in optimum usage of dipping sonar for anti-submarine helicopter.