An ink jet printing apparatus that can inhibit the possible degradation of image quality caused by variation in the conveyance amount of a print medium is provided. The ink jet printing apparatus includes a detection section detecting the conveyance amount of the print medium, and a print head position adjusting section slightly moving a print head in a conveyance direction of the print medium. The print head position adjusting section adjusts the position of the print head in the conveyance direction according to an error in the conveyance amount of the print medium detected by the detection section. Thus, printing can be performed at the head position adjusted with the error in conveyance amount taken into account. Therefore, the possible degradation of the image quality caused by a conveyance variation can be inhibited.