Abstract: A sanitary cat litter box and method of use. The sanitary cat litter box comprises a box top sized to frictionally fit onto a box bottom, an impervious bag sized to fit into the box bottom, and at least one sieve bag nested in the impervious bag. The box has a box mouth and a box aperture. The impervious bag has an impervious bag mouth co-extensive with the box mouth and an impervious bag aperture co-extensive with the box aperture. Each sieve bag has a sieve bag mouth co-extensive with the box mouth and a sieve bag aperture co-extensive with the box aperture. Means is provided to hold the corresponding box, impervious bag, and sieve bag mouths together, and to hold the corresponding box, impervious bag, and sieve bag apertures together. In use, the sieve bag(s) and impervious bag are placed within the box bottom, and the corresponding apertures attached. Cat litter is placed in the uppermost sieve bag, the corresponding mouths are attached, and the box top is installed on the box bottom.