Abstract: To realize the stable control of autonomous underwater vehicle（AUV）in underwater, an obstacle avoidance and attitude control algorithm was proposed based on fuzzy algorithm. By analyzing the condition of AUV in the horizontal plane and vertical plane, the fuzzy algorithms for obstacle avoidance and attitude control were constructed respectively, and the corresponding control systems were designed. The control system was mainly composed of two fuzzy controllers. The left, right and diving accelerations of AUV were output by the fuzzy controller, and the velocity was approximated by the fuzzy logic system. The obstacle avoidance and attitude control of AUV horizontal plane and vertical plane were realized by the velocity information of AUV. The simulation scene was constructed by placing obstacles in different positions, and Matlab simulation experiment was adopted. The simulation results show that the obstacle avoidance and attitude control method based on fuzzy algorithm can meet the design requirements.