The present invention provides a fixing device that can interrupt power supply to the resistive heat layer more reliably than the conventional technology, for example, at occurrence of abnormality. Electrodes 52a and 52b are provided on a circumferential surface of a fixing roller that includes a resistive heat layer that generates heat by receiving power supply, and power is supplied to the resistive heat layer when power supplying electrodes 54a and 54b that are electrically connected to an electric power source 55 are slidingly in contact with the electrodes 52a and 52b. An insulating tape 522a is attached on the electrode 52a, and the drive controller 59 rotates a motor 58 until the electrode 52a and the insulating tape 522a are in contact with each other, so that power supply to the resistive heat layer is interrupted.