The invention discloses a curve fitting-based maximum torque current control method. According to a vector control principle, an electromagnetic torque equation of a motor is simplified, and d-axis and q-axis current components of the motor are constant values in a steady-state condition; the equation is expanded by using a newton iteration method to obtain a partial derivative matrix, and a convergence condition is set; a corresponding curve relationship between electromagnetic torque and a d-axis current component function is obtained by using a numerical value analysis method in Matlab, the curve is close to a single branch of a quadratic curve, equivalent three-segment quadratic curve synthesis is carried out and simulated approaching is carried out by adopting a least square method; and a continuous function relationship is built by the electromagnetic torque and the d-axis current component of a stator, and the d-axis component can be quickly output. The curve fitting-based maximum torque current control method has the beneficial effects that the dependence on parameters of the motor is eliminated, the data memory capacity of an original system is reduced, the operating rate is increased, the performance of the system is improved, the minimum current under the maximum torque is optimized and the efficiency of a motor control system is improved.