An image forming apparatus, includes an image reader with an original document table. An image reading part has a light source, a light-receiving part, a reflection part, and a carriage that supports the light source or the reflection part. A cover covers a replacement member and is opened/closed integrally with the image reader. A main body accommodates an operation part for performing operations based on image data. An axis connects the image reader to the main body and turnably supports the image reader and the cover in approaching/separating directions with respect to the main body. An open/close detector detects an open/closed state of the image reader and the cover and a movement controller moves the carriage in a sub-scanning direction. When the image reader and the cover are open, the movement controller moves the carriage to a retreat position that is outside the original document table.