This invention provides an electronic document update notification device for notifying a user of update information of an electronic document including: a updated document name generating part 170 for generating a updated document name based on a stylized document name; a document data obtaining part 150 for obtaining document data after update based on the updated document name; a difference extracting part 180 for extracting difference data between document data before update and the document data after update; and an update information creating part 190 for creating an update information notification based on the difference data. This makes it possible to notify a user of the update information of the electronic document even when a document after update is created with the document name with the document name before update changed according to a predetermined rule, at the time of update of the electronic document.