A fixing device thermally fixes an unfixed image on a recording sheet by passing the recording sheet through a fixing nip. The fixing device has: a heat-generating endless belt; a first pressure member inside a running path of the endless belt; a second pressure member pressing the endless belt against the first pressure member from outside the running path to form the fixing nip, and a pair of power feeders. The endless belt includes: a circumferential resistive heat layer that generates heat upon receiving electric current; and a first electrode and a second electrode flanking a sheet passing area of the circumferential surface of the endless belt. Each electrode is composed of a pair of electrode layers, one on the inner and another on the outer circumferential surface of the resistive heat layer. Each power feeder is in contact with both the electrode layers of a different electrode.