The present invention is to provide a printing apparatus capable of correctly detecting an origin of a conveying roller for conveying a print medium at the time of its rotation with a simple configuration that does not accompany an increase of cost. For this purpose, the printing apparatus is equipped with a lock mechanism (a lock link lever) for stopping rotation of the conveying roller at a predetermined rotational position and saves a count value of a rotation amount of the conveying roller when the conveying roller is locked by the lock mechanism concerned as origin information. After this, driving of the conveying roller is controlled based on the saved origin information and a phase of rotation of the conveying roller obtained from the count value of the conveying roller.