To provide a device and a method for detecting the abnormality of an IPM, which can display distinctively that the abnormality signal outputted by the IPM expresses overheat abnormality or expresses other abnormality.

The receiver 11 of an IPM abnormality detector 10 receives the abnormality signal from an IPM 21, and informs a drive controller 31, a display controller 15, and a timer 12 of it. The drive controller 31 stops an injection molding machine 20, and the IPM 21 resets itself. Moreover, the display controller makes an indicator 14 display 'the occurrence of abnormality'. When the timer arrives, a determing section 13 determines whether the receiver still receives a reception signal or not. In case that it has determined that the receiver still receives the abnormality signal, it informs the display controller of it. The display controller makes the indicator display 'the occurrence of overheat abnormality'.