A new VATG system is constructed to eliminate the accumulated error in the midcourse guidance.The visual pose estimation method is introduced to get the state parameters of the missile.The unscented Kalman filter（UKF）is used to fuse the information of the vision system and the inertial navigation system.The simulation control model of the vision aided terminal guidance is built up.The experimental results show that the precision and reliability of the terminal guidance system are significantly increased using the proposed method.