In this paper, the character on underwater environment, dynamics model and control strategies of AUVs are analyzed. Dynamics model of AUVs are highly nonlinear, multi-freedom coupled, and time varying. The environment disturbance of the ocean to includes wave, ocean current and imbalance force. In order to reduce the effect of the imbalance force and the ocean current to AUVs, a robust adaptive control strategy based on backstepping is presented. The robust adaptive control strategy is applied to horizontal control of AUVs and realizes the horizontal dynamic positioning and target tracking of AUVs. We have made some computer simulations based on AUV CR-02, and compared the control strategy with traditional PID control strategy. The performance has obviously been improved on precision of dynamic positioning and target tracking, especially under serious disturbance.