An accelerator device includes a pedal pad and a strain gauge. When a driver of a vehicle having the accelerator device depresses the pedal pad, the pedal pad is deformed in a direction of a blank arrow. The strain gauge senses the displacement amount of the pedal pad in the direction of the blank arrow and outputs an electric signal, which corresponds to the displacement amount, to an outside as the depression amount of the accelerator device. When the driver removes a foot from the pedal pad, the pedal pad returns to a state of the pedal pad that is not depressed by the driver. Therefore, it is possible to limit occurrence of that the depression amount of the pedal pad becomes an unintended value due to, for example, catching of the pedal pad by a floor mat. As a result, the accelerator device can reliably sense the depression amount.