A printer comprising: a conveying device that conveys a tablet; a first image pickup device that picks up an image of a face facing one side in an orthogonal direction to a conveyance direction of the tablet while being conveyed; a first checking section that checks the face facing the one side of the tablet 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 face facing the one side of the tablet while being conveyed; a second image pickup device that picks up an image of a face facing the other side in the orthogonal direction of the tablet while being conveyed; a second checking section that checks the face facing the other side of the tablet based on the image picked up by the second image pickup device; a second printing device that is disposed at a downstream side of the second image pickup device and that performs printing on the face facing the other side of the tablet while being conveyed, characterized by a first dividing line judging section that judges whether or not there is a groove-shaped dividing line on the one side based upon the image picked up by the first image pickup device; and a first dividing line position calculating section that calculates the position of the dividing line based upon the image picked up by the first image pickup device; wherein the second printing device performs printing on the face facing the other side in the orthogonal direction of the tablet based upon the position calculated by the first dividing line position calculating section, while being conveyed. a conveying device that conveys a tablet; a first image pickup device that picks up an image of a face facing one side in an orthogonal direction to a conveyance direction of the tablet while being conveyed; a first checking section that checks the face facing the one side of the tablet 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 face facing the one side of the tablet while being conveyed; a second image pickup device that picks up an image of a face facing the other side in the orthogonal direction of the tablet while being conveyed; a second checking section that checks the face facing the other side of the tablet based on the image picked up by the second image pickup device; a second printing device that is disposed at a downstream side of the second image pickup device and that performs printing on the face facing the other side of the tablet while being conveyed, characterized by a first dividing line judging section that judges whether or not there is a groove-shaped dividing line on the one side based upon the image picked up by the first image pickup device; and a first dividing line position calculating section that calculates the position of the dividing line based upon the image picked up by the first image pickup device; wherein the second printing device performs printing on the face facing the other side in the orthogonal direction of the tablet based upon the position calculated by the first dividing line position calculating section, while being conveyed.