An image forming apparatus includes an image forming unit configured to perform printing and an initializing process, a casing formed with an opening and accommodating the image forming unit, a cover configured to open and close the opening, a detecting unit configured to detect whether the cover is in an opened state or a closed state, a measuring unit configured to measure an opening degree of the cover in the opened state, and a controller configured to control an initializing process of the image forming unit according to the opening degree of the cover in the opened state, when the detecting unit detects that the cover is changed from the closed state to the open state and that the cover is returned to the closed state.