To ensure easy control of the engine output by a driver in an abnormality processing device for an accelerator sensor detecting abnormality of the sensor outputting a signal according to an accelerator depression amount, and performing the processing of the abnormality.

The device has an acceleration member operated by the driver, the sensor outputting the signal according to an operating amount of the acceleration member, an abnormality detection means detecting the abnormality of the sensor, an idle side switch which turns on at the time of no-operation of the acceleration member, a full side switch which turns on at the time of the maximum operation of the acceleration member, and a control means which sets up an accelerator opening when the abnormality of the sensor is detected with the abnormality detection means. The control means inputs gear shift position of a shift lever, and sets up the accelerator opening according to the gear shift position.