Abstract: For the angular position and attitude control system of the stabilized platform of rotary steering drilling tool,the relationship among the dynamic parameters of rotation motion in the angular position control system and the characteristics of rotation angle control are analyzed.A control algorithm is introduced to solve these special control requirements.A method is presented to describe dynamic response curves in the polar coordinates and it is very suitable for the angular position control systems.A fuzzy control system for the drilling tool stabilized platform is designed,which uses the angular position and angular velocity as the input variables and the increment of driving electric current as the output variables.The presented fuzzy control system can not only solve the problem of the relation between angular position and direction of rotation,but also get better robustness and anti-interference ability than conventional control methods,so it is more suitable for the down-hole working situations in oil-well drilling engineering.