The living activity inference device according to the present invention includes: an obtainer configured to obtain an energy consumption of an electric appliance; an appliance operation detector configured to identify an operational state of the electric appliance based on the energy consumption obtained by the obtainer; and an activity inferrer configured to perform an inference process of determining which one of a plurality of living activities predetermined a current living activity corresponds to, based on existing information including the operational state of the electric appliance identified by the appliance operation detector and a past living activity.