A cognitive function evaluation device includes: an obtainment unit that obtains use information indicating a state of use of a toilet by a subject; a calculation unit that calculates a total number of times of use of a toilet by the subject, based on the use information obtained by the obtainment unit; an evaluation unit that evaluates a cognitive function of the subject, based on the total number of times of use calculated by the calculation unit; and an output unit that outputs a result of evaluation performed by the evaluation unit.