In order to improve the efficiency and control performance, reduce operation intensity of lorrymounted crane, the control performance of the hydraulic system of the lorrymounted crane was analyzed, and an adaptive sliding mode control method was proposed. An adaptive sliding mode controller was designed by analyzing the working principle and mathematical model of the hydraulic control system of the lorrymounted crane; the control characteristics of the adaptive sliding mode control system and PID control system were compared and analyzed. The results show that the hydraulic control system with adaptive sliding mode control has good stability, dynamic control performance and servo tracking performance.