Abstract: Based on robust control design method, a variable structure guidance is proposed for autonomous underwater vehicle (AUV) during the guiding course with terminal impact angle constraint. Considering the intercept geometry, a sliding mode controller is proposed for controlling the line of sight angle rate and the impact angle, based on the principle which controls the line of sight angle rate to approach zero and the terminal angle to approach the expected value more quickly as the distance decreases. Simulation results show that, with the application of the proposed method, small miss distance is achieved and the expected impact angle is reached. In addition, the system is robust to the target maneuvering.