This litter box (1) comprises: an upper container (20) having a plurality of holes (21a) formed in the bottom thereof, the holes extending vertically through the bottom； a lower container (30) which is provided with a receptacle (31) for receiving excreta passing through the plurality of holes (21a) and is not affected by the weight of the upper container (20)； and an output unit (41) for outputting a signal which varies with the amount of the excreta received by the receptacle (31).
