Provided is a can-printing apparatus equipped with a can inspection device capable of density and printing deviation measurements necessary for improving the printing precision of the printer. An image-processing unit (53) for processing an image that has been photographed is provided with: an image inspection means (54) for comparing a can with a master image using an image of the whole can taken with a first camera to check whether the can is printed correctly; a density measurement means (55) for measuring the density of each color at designated positions similarly using the image of the whole can taken with the first camera; and a printing deviation measurement means (56) for measuring, using an image of the open end of the can taken with a second camera, deviations with respect to positions set for printing deviation inspection marks printed for each color on the open end of the can.