The Hall current sensor is often used in the motor current sampling circuit with full localization requirements. However, there is still a certain gap between domestic technology and imported products, which makes it vulnerable to the influence of circuit electronic circuits, resulting in large random noise in current sampling data. In order to improve the accuracy of current sampling and improve the stability of torque control, this paper proposes a high-precision current detection method combining hardware circuit filtering and software filtering. Firstly, the selection of RC resistance and capacitance is analyzed and the filter circuit is built. Then, the software filtering method of sliding average value is proposed. Through experimental verification, this method can effectively suppress the random noise of the Hall current sensor and improve the stability of the control system.