An image forming apparatus includes an image bearing member, a frame member including a support surface and made of metal, an exposure unit disposed such that an emission direction in which the light is emitted to the image bearing member is inclined with respect to the support surface, a support member made of metal and configured to support the exposure unit that is in an inclined posture with respect to the support surface, and a positioning member made of resin and configured to be in contact with the exposure unit and position the exposure unit. The support surface of the frame member is in contact with at least one of the support member or the positioning member, and wherein the exposure unit is configured to be attached to the frame member via the support member and the positioning member.