A fixing device includes a roller, an endless belt, and a heat generating member disposed in a space inside the endless belt, extending in a width direction of the endless belt, and pressing the endless belt against the roller. A sheet is passed through a nip formed between the roller and a portion of the endless belt pressed by the heat generating member, such that an image on the sheet is fixed thereto. The heat generating member includes first and second heat generating portions that are adjacent to each other along the width direction and independently operable from each other. A boundary of the first and second heat generating portions extends in a direction inclined with respect to a sheet conveying direction.