A printer of the present invention includes a first image pickup device that picks up an image of one side of an object, a first checking section that checks the one side of the object based on the image picked up by the first image pickup device, a first printing device that is disposed at a downstream side of the first image pickup device and that performs printing on the one side of the object while being conveyed, a second image pickup device that picks up an image of the other side of the object while being conveyed, a second checking section that checks the other side of the object based on the image picked up by the second image pickup device, and a second printing device that is disposed at a downstream side of the second image pickup device and that performs printing on the other side of the object while being conveyed.
