The check deposit apparatus of the present invention comprises an insertion part that is used to insert a check from outside for deposit, a feed part furnished with a feed roller that feeds the placed check along a feed path, an alignment part furnished with an alignment roller that feeds the check fed from the feed part to one side of the feed path and also aligns it, a check reading part that reads information of the check that has been aligned by the alignment part, first and second sensor groups that judge whether the check inserted into the insertion part has a specification that enables it to be fed and processed toward the alignment part normally, a third sensor group that judges whether the check aligned in the alignment part has a specification that enables it to be read and processed normally in the check reading part, and a control part that judges whether to deposit or return the check in question based on the information sensed by the first and second group or third sensor group. According to the invention, a check that has been erroneously placed or does not meet specifications may be readily returned to the user.