An image forming apparatus includes a photosensitive member, an exposure device, and a developing device. A sensor detects a toner image formed by the developing device to output density information, and a supply device supplies developer to the developing device. In addition, a controller controls the supply device on the basis of a detection result of a supply control toner image formed by the exposure device, a storing portion stores the detection result, and an exchange detecting portion detects information for discriminating exchange of the photosensitive member and the developing device. When the developing device is not exchanged but the photosensitive member is exchanged, the controller executes an operation in a mode in which the controller adjusts an exposure condition for forming the supply control toner image by the exposure device after exchange of the photosensitive member.