An image forming apparatus includes a control unit configured to cause an image forming unit to form an adjustment image on an image bearing member, and a detection unit configured to detect the adjustment image, wherein the control unit controls gradation for forming an image by the image forming unit based on a detection result provided by the detection unit, and wherein, when causing the image forming unit to form a first adjustment image on the image bearing member at a photosensitive member and to subsequently form a second adjustment image that is different from the first adjustment image, the control unit causes the image forming unit to form the second adjustment image at a position different from a position for forming the first adjustment image in a longitudinal direction of the photosensitive member.