An image heating apparatus includes a hollow image heating roller having a through hole at one axial end portion side thereof; a bearing fitted around the roller; a heat insulating bush fitted around the roller between the roller and the bearing; a retaining ring for preventing the heat insulating bush from moving relative to the roller; an annular spacer provided between the heat insulating bush and the retaining ring, the annular spacer being provided with an inwardly protruded key portion engageable with the through hole.