A fixing device for fixing an image onto a recording sheet by applying heat and pressure to the recording sheet and the image thereon while the recording sheet is passing through a fixing nip, the fixing device comprising: a pressure belt movable in a revolving motion; a rotatable fixing roller; and a pressure member for pressing an inner circumferential surface of the pressure belt toward the fixing roller, the fixing nip being formed between the fixing roller and the pressure belt while an elastically deformable surface of the fixing roller in rotation is arranged to be brought into contact with an outer surface of the pressure belt by a pressure applied by the pressure member to the inner circumferential surface of the pressure belt, the pressure member including: an elastic pressure member for applying pressures at its elastic pressure surface to the fixing roller to cause a pressure distribution in which a greater pressure is applied to a center of the fixing roller than to each of ends thereof, the center and the ends being along an axis direction of the fixing roller; and a hard pressure member that is disposed parallel to the elastic pressure member on downstream side of the elastic pressure member in a direction of the revolving motion of the pressure belt and is arranged to apply pressures to the fixing roller to cause a pressure distribution in which a greater pressure is applied to each of the ends of the fixing roller than to the center of the fixing roller, wherein the pressure member further includes a main pressure part that is arranged to cause the urging force to act on both of the elastic pressure member and the hard pressure member, wherein the main pressure part has a supporting surface arranged to support the elastic pressure member, characterised in that the supporting surface has a shape in which the supporting surface rises from ends thereof toward a center thereof to form a projection; with a center flat surface so that the center is closer to the fixing roller than the ends, the center and the ends being along the axis direction of the fixing roller, and the elastic pressure member is in a shape of plane-parallel plates and deforms following the shape of the supporting surface when the elastic pressure member is in the state of not pressing the fixing roller, wherein a projection length of the elastic pressure surface in the state where the elastic pressure member has been translated to separate from the fixing roller is in a range from 0.1mm to 0.6mm, and the length of the center flat surface along an axis direction of the fixing roller is in a range from 1/3 to 1/2 the entire length of the supporting surface in the axis direction of the fixing roller. a pressure belt movable in a revolving motion; a rotatable fixing roller; and a pressure member for pressing an inner circumferential surface of the pressure belt toward the fixing roller, the fixing nip being formed between the fixing roller and the pressure belt while an elastically deformable surface of the fixing roller in rotation is arranged to be brought into contact with an outer surface of the pressure belt by a pressure applied by the pressure member to the inner circumferential surface of the pressure belt, an elastic pressure member for applying pressures at its elastic pressure surface to the fixing roller to cause a pressure distribution in which a greater pressure is applied to a center of the fixing roller than to each of ends thereof, the center and the ends being along an axis direction of the fixing roller; and a hard pressure member that is disposed parallel to the elastic pressure member on downstream side of the elastic pressure member in a direction of the revolving motion of the pressure belt and is arranged to apply pressures to the fixing roller to cause a pressure distribution in which a greater pressure is applied to each of the ends of the fixing roller than to the center of the fixing roller, wherein the pressure member further includes a main pressure part that is arranged to cause the urging force to act on both of the elastic pressure member and the hard pressure member, wherein the main pressure part has a supporting surface arranged to support the elastic pressure member, characterised in that the supporting surface has a shape in which the supporting surface rises from ends thereof toward a center thereof to form a projection; with a center flat surface so that the center is closer to the fixing roller than the ends, the center and the ends being along the axis direction of the fixing roller, and the elastic pressure member is in a shape of plane-parallel plates and deforms following the shape of the supporting surface when the elastic pressure member is in the state of not pressing the fixing roller, wherein a projection length of the elastic pressure surface in the state where the elastic pressure member has been translated to separate from the fixing roller is in a range from 0.1mm to 0.6mm, and the length of the center flat surface along an axis direction of the fixing roller is in a range from 1/3 to 1/2 the entire length of the supporting surface in the axis direction of the fixing roller.