The invention provides a loop and a method for converting an operating state of an alternating current contactor by a contact switch contact. The loop comprises an AC power supply, wherein the output side of the AC power supply is connected with a power-on button; a control loop and other electronic circuits are arranged at the output end of the AC power supply in parallel; and a parallel circuit of the control loop and other electronic circuits is connected with the power-on button in series at the two ends of the AC power supply. By virtue of the technical scheme, the beneficial effects as follows are achieved: a conversion circuit is formed by matching of a the contact switch and a power electronic element; alternating current and direct current operating ways are switched in time in a module fault condition; fault conversion and overvoltage resistance functions are added in the control loop of the contactor, so that power supply continuity of the contactor is ensured; and the loop and the method are of great significance to the reliable, stead and economical operation of a power distribution network.