A fixing unit comprising: a heating rotary belt; a pressing member that is disposed in an inner portion of the heating rotary belt, and that abuts with an inner surface of the heating rotary belt; a pressing rotor that is disposed facing the heating rotary belt, and that is configured to form a fixing nip with the heating rotary belt by sandwiching the heating rotary belt with the pressing member; an induction coil separated from an external surface of the heating rotary belt and disposed along the external surface, and configured to generate a magnetic flux to generate heat in the heating rotary belt; a magnetic core portion configured to form a magnetic path for the magnetic flux generated by the induction coil, characterized in that the fixing unit further comprises: a regulating portion configured to regulate the deformation of the heating rotary belt by abutment with the external surface of the heating rotary belt; and a supporting member disposed on a side of the heating rotary belt relative to the induction coil to thereby face the external surface of the heating rotary belt, and support the induction coil; wherein the regulating portion is disposed on the supporting member, and regulates the deformation of the heating rotary belt by abutment with the external surface of the heating rotary belt to keep a distance between the induction coil and the external surface of the heating rotary belt constant, wherein the supporting member is elongated in an orthogonal direction that is orthogonal to a conveyance direction of a transfer material, and the regulating portion is disposed on both ends of the supporting member in the orthogonal direction, further comprising a non-paper passing region formed on an external surface of the heating rotary belt, and is a region on an outer side of a region defined by passage of a sheet-shaped transfer material having a maximum length in the orthogonal direction that is conveyed to the fixing nip, wherein the regulating portion is formed to project from the supporting member so to abut with the non-paper passing region. a regulating portion configured to regulate the deformation of the heating rotary belt by abutment with the external surface of the heating rotary belt; and a supporting member disposed on a side of the heating rotary belt relative to the induction coil to thereby face the external surface of the heating rotary belt, and support the induction coil; wherein the regulating portion is disposed on the supporting member, and regulates the deformation of the heating rotary belt by abutment with the external surface of the heating rotary belt to keep a distance between the induction coil and the external surface of the heating rotary belt constant, wherein the supporting member is elongated in an orthogonal direction that is orthogonal to a conveyance direction of a transfer material, and the regulating portion is disposed on both ends of the supporting member in the orthogonal direction, further comprising a non-paper passing region formed on an external surface of the heating rotary belt, and is a region on an outer side of a region defined by passage of a sheet-shaped transfer material having a maximum length in the orthogonal direction that is conveyed to the fixing nip, wherein the regulating portion is formed to project from the supporting member so to abut with the non-paper passing region.