This research proposed a high-order disturbance estimation using Kalman filter for precise reaction-torque control. The proposed method is able to realize the reaction torque control system by using the proportional-derivative controller. It is confirmed that the proposed proportional-derivative controller of reaction torque can improve control system performance without enhancing the noise effect. This is because estimated variables by the proposed Kalman filter based high order disturbance/reaction torque observer are utilized in the PD controller. The observer can estimate the disturbance/external torque and its time derivative with lower noise level than the conventional disturbance observers (DOBs) or reaction torque observers (RTOBs). Experimental results validate the proposed method.