This paper presents a fuzzy tuning approach to sliding mode control for tracking-performance enhancement in a class of nonlinear systems. The sliding surface can rotate or shift in the phase space in such a direction that the tracking behaviour can be improved. It is shown that with arbitrary initial conditions, the reaching time and tracking error in the approaching phase can be significantly reduced. Chattering can also be reduced by fuzzy tuning of the controller parameters. A two-degree-of-freedom robotic manipulator subject to external disturbances is simulated to demonstrate the validity of the proposed method.