Abstract: The underwater vehicle is a new type of tactical weapons whose response of dynamic characteristics varies with operational conditions in the course of attack.Thus,the autopilot must be adjusted with the flying conditions.We applied the newest linear parameter varing(LPV)technique dealing with the large-range varying parameter systems to design the gain scheduling H_∞ controllers for the lateral-directional axis of underwater vehicle via solving three linear matrix inequalities(LMIs).The simulation demonstrated that the characteristics of the control system desiged by the LPV technique is better than the general frozen-parameter method.