An image heating apparatus for heating an image formed on a sheet includes an endless belt; a roller contactable with the endless belt to form a nip for nipping and feeding the sheet; a heater provided inside the endless belt; a guiding member, provided inside the endless belt, for guiding rotation of the endless belt; a reinforcing member, provided between the endless belt and the heater in a radial direction of the heater, for reinforcing the guiding member, the reinforcing member being provided with an opening to permit radiant light from the heater to reach the endless belt; a protecting member, provided between the heater and the reinforcing member in the radial direction so as to oppose the endless belt through the opening, thus preventing contact between the endless belt and the heater.