Abstract: We propose a novel adaptive sliding mode control algorithm for manipulator systems based on a disturbance observer. This mode control algorithm is successfully used in the motion control of manipulator systems to improve control precision and robustness. Considering external disturbance, we develop a new disturbance observer based on non-singular terminal sliding mode to compensate for control input to enhance precision. Then, we propose a continuous adaptive sliding mode control algorithm with a disturbance observer which can overcome chattering and improve control precision. Closed-loop stability is proved by Lyapunov theory. Matlab simulation results verify that the proposed approach has high precision and strong robustness in the presence of external disturbance and system uncertainty.