In this paper, an adaptive fuzzy backstepping controller is presented for the hydraulic gap system. The appropriate Lyapunov functions are selected to reduce the backstepping design steps, which solves the problem of “explosion of calculation” among the backstepping design process. Adaptive fuzzy systems are employed to eliminate the impacts of uncertain parameters and load disturbances. The convergence of the system tracking error is proved and the adaptive laws of uncertain parameters are given. The simulation results show that the controller can achieve fast, accurate dynamic performance.