In this paper, a class of gun control system of tank is considered with uncertain parameters and the backlash-like hysteresis which modeled by a differential equation. An adaptive control law is designed with backstepping technique. Compared to exist results on tank gun control problem , in our control scheme, the effect of backlash hysteresis is considered completely than to be linearized simply and no knowledge is assumed on the uncertain parameters. the stability of closed loop system and the tracking performance can be guaranteed by this control law. Simulation studies show that this controller is effective.