Abstract: A cage includes a base having an opening and two accesses and a cover having an opening and two accesses aligned with the opening and the accesses of the base. A door is pivotally coupled between the base and the cover for enclosing the opening, two grids engaged in the accesses of the base and the cover, and two lids each having two halves pivotally coupled together. The cage includes a pan disposed in the bottom portion for collecting discharges of pets, and the cage can be easily assembled.