The utility model discloses a motor protector capable of protecting motor against reversal, phase failure and overload. Under the condition of without any triode, diode and resistor, the utility model adopts a novel circuit to solve the problems of the burning out of a motor caused by phase failure and overload while operating and the reversal of the motor caused by the changes of the phase order of a three-phase power supply. The utility model can solve the reversed orders of the wiring modification of an electric network and a motor caused by the phase failure and the overload of the motor, can adjust the phase orders in time, and can guarantee the motor to operate in a normal direction. The utility model has the advantages of advanced structure, low cost, convenient operation, simple production and fewer elements.