Abstract: A work estimation device (200) includes a watching region estimation unit (220), an object detection unit (210), a contact degree calculation unit (230), and a work estimation unit (250). The watching region estimation unit (220) estimates a watching region which is a region a user watches, with using information indicating a line of sight of the user. The object detection unit (210) detects, from a video that shows a work object the user is using and at least one target candidate object which is a candidate for a work target of the user, the work object and the at least one target candidate object. The contact degree calculation unit (230) calculates a contact degree indicating a degree of contact between the work object and each target candidate object which is included in the at least one target candidate object, on a basis of the watching region. The work estimation unit (250) estimates work of the user on a basis of the work object and the contact degree.