The invention discloses an interturn short circuit fault detection method used for a five-phase OWFTFSCW-IPM motor. The interturn short circuit fault detection method comprises steps that step1: actual current of a five-phase winding detected by a current sensor is adopted; step2: the estimated torque value of the motor is acquired by using a torque calculation formula; step3: the actual torque output value of the motor is measured by a torque sensor; step 4: the actual output torque of the motor is subtracted by the estimated torque to acquire torque deviation; step 5: the alternating current component of the torque deviation is filtered by a filter to acquire the direct current component of the torque deviation, and when the direct current component exists, the interturn short circuit fault occurs. The interturn short circuit fault detection method has advantages of simple realization, low requirements on controller, small calculated amount, simple operation, low misjudgement rate, and abilities of facilitating engineering realization, and detecting occurrence of interturn short circuit faults effectively in motor dynamic process.