An embodiment of this invention solves a problem about a precision drop of registration adjustment of a range detection method due to variations of a registration state depending on a position associated with a carriage scanning direction. In that embodiment, reference and adjustment patterns are formed to be juxtaposed in a nozzle array direction to detect a position shift between patterns in the main scanning direction. In this case, coarse registration adjustment is executed by the range detection method, and its adjustment result is applied to a printing apparatus. After that, fine registration adjustment is executed by a density method, and results of the two adjustment methods are finally reflected.