A fixing device comprising: a fixing belt arranged rotatably around a rotation axis; a pressuring member arranged rotatably and configured to come into pressure contact with the fixing belt so as to form a fixing nip; a meandering restriction member arranged outside the fixing belt in the direction of the rotation axis; a pressing member configured to press the fixing belt to the pressuring member side; a heat source arranged at an inner circumferential side of the fixing belt and arranged at an upper side of the pressing member and configured to radiate a radiant heat; and a reflecting member arranged at a lower side of the heat source and configured to reflect the radiant heat radiated from the heat source to an inner circumferential face of the fixing belt; wherein the fixing belt has: a passing region through which a recording medium passes; and a non-passing region arranged outside the passing region in a direction of the rotation axis, the reflecting member has: a first reflecting part arranged at an inner circumferential side of the passing region; and a second reflecting part arranged outside the first reflecting part in the direction of the rotation axis and arranged at an inner circumferential side of the non-passing region, roughness of a face at the heat source side of the second reflecting part is larger than roughness of a face at the heat source side of the first reflecting part, wherein the face at the heat source side of the first reflecting part is subjected to a mirror surface treatment, wherein at least a part of the second reflecting part is arranged between the heat source and the meandering restriction member. a fixing belt arranged rotatably around a rotation axis; a pressuring member arranged rotatably and configured to come into pressure contact with the fixing belt so as to form a fixing nip; a meandering restriction member arranged outside the fixing belt in the direction of the rotation axis; a pressing member configured to press the fixing belt to the pressuring member side; a heat source arranged at an inner circumferential side of the fixing belt and arranged at an upper side of the pressing member and configured to radiate a radiant heat; and a reflecting member arranged at a lower side of the heat source and configured to reflect the radiant heat radiated from the heat source to an inner circumferential face of the fixing belt; wherein the fixing belt has: a passing region through which a recording medium passes; and a non-passing region arranged outside the passing region in a direction of the rotation axis, the reflecting member has: a first reflecting part arranged at an inner circumferential side of the passing region; and a second reflecting part arranged outside the first reflecting part in the direction of the rotation axis and arranged at an inner circumferential side of the non-passing region, roughness of a face at the heat source side of the second reflecting part is larger than roughness of a face at the heat source side of the first reflecting part, wherein the face at the heat source side of the first reflecting part is subjected to a mirror surface treatment, wherein at least a part of the second reflecting part is arranged between the heat source and the meandering restriction member. a passing region through which a recording medium passes; and a non-passing region arranged outside the passing region in a direction of the rotation axis, the reflecting member has: a first reflecting part arranged at an inner circumferential side of the passing region; and a second reflecting part arranged outside the first reflecting part in the direction of the rotation axis and arranged at an inner circumferential side of the non-passing region, roughness of a face at the heat source side of the second reflecting part is larger than roughness of a face at the heat source side of the first reflecting part, wherein the face at the heat source side of the first reflecting part is subjected to a mirror surface treatment, wherein at least a part of the second reflecting part is arranged between the heat source and the meandering restriction member. a first reflecting part arranged at an inner circumferential side of the passing region; and a second reflecting part arranged outside the first reflecting part in the direction of the rotation axis and arranged at an inner circumferential side of the non-passing region, roughness of a face at the heat source side of the second reflecting part is larger than roughness of a face at the heat source side of the first reflecting part, wherein the face at the heat source side of the first reflecting part is subjected to a mirror surface treatment, wherein at least a part of the second reflecting part is arranged between the heat source and the meandering restriction member.