A position information acquiring unit acquires position information relating to positions of a plurality of body parts of a player. A determination unit determines whether or not the at least one of the plurality of body parts exists within a determination region including the reference position at a time point corresponding to the reference time. A body part information acquiring unit acquires body part information relating to a kind of the at least one of the plurality of body parts determined to exist within the determination region. An evaluation unit evaluates gameplay of the player based on the kind of the at least one of the plurality of body parts acquired by the body part information acquiring unit.