Although the general sliding mode control has the robust property, bounds on the disturbances and parameter variations should be known a priori to the designer of the control system. Fuzzy logic provides an effective way to design a controller of the system with disturbances and parameter variations. Therefore, combination of the best feature of the fuzzy logic control and the sliding mode control is considered. The adaptive fuzzy variable structure controller developed in this paper employs fuzzy controller with nonlinear sliding mode. Therefore, the resulting system can resolve the conflict between the opposing requirements of static and dynamic accuracy that are encountered when designing the linear sliding mode. A variable length pendulum system is used to demonstrate the availability of the proposed approach.