This paper presents a novel control strategy based on adaptive sliding mode control. The proposed adaptation law allows adjusting the control gain by taking into account the effects of bounded uncertainties and perturbations with unknown bounds. The main advantage of the proposed adaptive sliding mode control algorithm is in adjusting the control gain without its overestimation in the presence of the bounded perturbations with the unknown bounds. This yields the reduction of chattering. The control law is applied for position-pressure control of electropneumatic actuator experimental setup.