A fixing device includes a separation plate, an arm member, an axial member, a support bracket, and a temperature sensor. The separation plate is disposed spaced apart from a peripheral surface of a heating rotating body by a predetermined clearance distance K2. The separation plate separates a recording medium having passed through between the heating rotating body and a pressing roller from the heating rotating body. The arm member holds the temperature sensor by using one end portion thereof. The axial member extends in parallel to a rotating shaft of the heating rotating body and rotatably supports the other end portion of the arm member. The support bracket supports the separation plate. The support bracket is provided with a sensor abutting portion that abuts the temperature sensor held by the arm member to restrict a clearance distance between the temperature sensor and the heating rotating body.