Provided is a contactor power saver, comprising a main power circuit, a current sampling circuit, an error amplification circuit, and a PWM control circuit, wherein the current sampling circuit samples a voltage signal of the main power circuit, and outputs a current sampling signal; the error amplification circuit compares the current sampling signal with a reference voltage, and outputs an error voltage signal; and the PWM control circuit detects the error voltage signal, outputs a drive signal with a constant frequency and a duty ratio proportional to that of the error voltage signal, and controls the turning on and turning off of a switch tube in the main power circuit. According to the present invention, a power factor value can be increased to approximately 0.9, and current of a contactor coil is constant under a wide-range input voltage. Various modules of the control circuit may be integrated, the circuit is simple, and the cost is low.