The invention relates to a non-linear compensation control method of a steam inlet regulating valve of a steam-driven water feeding pump. The method acquires opening command signals of regulating valves for controlling the rotating speed of a steam pump in the following manner: the quotient obtained by dividing the difference between a steam pump rotation speed command signal and a rotation speedfeedback signal by the total gain coefficient signal after inertia filtering is sequentially processed by a PID controller and a manual/automatic operation station module to obtain a comprehensive valve position signal, the difference between the comprehensive valve position signal and an output signal of a first analog quantity constant module is processed by a first high-low amplitude limiting module to obtain an HP opening degree command signal, and the comprehensive valve position signal is processed by a second high-low amplitude limiting module to obtain an LP opening degree command signal. According to the method, non-linear gain calculation logic is designed for three types of non-linearities respectively, and finally the three types of non-linearities are combined into a total gain coefficient in a product mode to compensate the gain of a steam pump rotating speed control system, so that centralized compensation of the three types of non-linearities is realized. The method caneffectively improve the control quality of the steam-driven water feeding pump, thereby avoiding caused steam pump rotating speed out-of-control faults.