Provided are a pharmaceutical packaging apparatus, a method of determining the remaining quantity of pharmaceutical packaging paper, and a pharmaceutical packaging paper roll, whereby it is possible to accurately determine the remaining quantity of residual pharmaceutical packaging paper. The apparatus is provided with : a roll support part (2) on which is mounted a core tube (201) of a pharmaceutical packaging paper roll (200); a sensor (24) furnished to the roll support part (2), for detecting a count value according to the amount of rotation; a wireless reader/writer (26) having an antenna (25) on the roll support part (2), and using this antenna (25) to write information to a core tube IC tag (202) furnished to the core tube (201), and to read information written thereto; an information generating unit (57a) for generating information to be written to the core tube IC tag (202); a remaining paper quantity estimating unit (57) for estimating the current remaining paper quantity, on the basis of the aforementioned information and dimension information about the core tube (201); and a controller (5) that selectively carries out a process to be performed in the event that a reference start point value has yet to be written to the core tube IC tag (202), or a process to be performed in the event that the value has been written.