An animal litter box having a front-back direction, a left-right direction, and an up-down direction, the animal litter box comprising: a litter-box main portion including an upper container and a lower container; the upper container including a plurality of holes (h) passing through the upper container in the up-down direction, the lower container including a reception portion, the reception portion being arranged to receive, in use, excrement that has passed through the plurality of holes (h); an output main portion including an output portion, the output portion including a top surface and a side wall, the top surface coming into contact with the litter-box main portion, the side wall extending from an edge of the top surface in the up-down direction, and the output portion being configured to output a signal in accordance with a magnitude of a force that acts on the top surface; characterized in that the animal litter-box further comprises: a position regulator including a litter-box-side regulating portion and an output-side regulating portion, the litter-box-side regulating portion disposed on the litter-box main portion, the output-side regulating portion disposed on the output main portion, the output-side regulating portion being a portion different from the side wall, a relative position between the litter-box main portion and the output main portion in at least one of the front-back direction and the left-right direction being regulated by the position regulator. a litter-box main portion including an upper container and a lower container; the upper container including a plurality of holes (h) passing through the upper container in the up-down direction, the lower container including a reception portion, the reception portion being arranged to receive, in use, excrement that has passed through the plurality of holes (h); the upper container including a plurality of holes (h) passing through the upper container in the up-down direction, the lower container including a reception portion, the reception portion being arranged to receive, in use, excrement that has passed through the plurality of holes (h); an output main portion including an output portion, the output portion including a top surface and a side wall, the top surface coming into contact with the litter-box main portion, the side wall extending from an edge of the top surface in the up-down direction, and the output portion being configured to output a signal in accordance with a magnitude of a force that acts on the top surface; the output portion including a top surface and a side wall, the top surface coming into contact with the litter-box main portion, the side wall extending from an edge of the top surface in the up-down direction, and the top surface coming into contact with the litter-box main portion, the side wall extending from an edge of the top surface in the up-down direction, and the output portion being configured to output a signal in accordance with a magnitude of a force that acts on the top surface; a position regulator including a litter-box-side regulating portion and an output-side regulating portion, the litter-box-side regulating portion disposed on the litter-box main portion, the output-side regulating portion disposed on the output main portion, the output-side regulating portion being a portion different from the side wall, a relative position between the litter-box main portion and the output main portion in at least one of the front-back direction and the left-right direction being regulated by the position regulator. the litter-box-side regulating portion disposed on the litter-box main portion, the output-side regulating portion disposed on the output main portion, the output-side regulating portion being a portion different from the side wall, a relative position between the litter-box main portion and the output main portion in at least one of the front-back direction and the left-right direction being regulated by the position regulator.