The present invention relates to a device of treating excretion of a cat. The device of treating excretion of a cat comprises: a case including an opening, through which the cat enters and exits, formed on a front surface as an upper case is combined with a lower case； a drum tiltedly installed on an inner side of the case and configured to separate an excrement treating material including excrement of the cat and sand while rotating by a driving force of a motor； a sand filter installed on an inner side of the drum to be able to rotate and configured to separately discharge the excrement of the cat and the excrement treating material； a driving unit installed on one side of the lower case by a motor bracket and including the motor configured to rotate the drum by the driving force and a rotary shaft； and a controller installed between the case and the drum and configured to sense entrance and exit of the cat using an optical sensor, an ultrasonic senor, and a weight sensor disposed on a rear surface side of the drum and on a drum opening and control the motor of the driving unit so as to treat the excrement. Thus, excrement and urine by the cat can be automatically treated. In addition, it is possible to selectively use excrement treating materials such as sand, wood pellets, and the like according to a preference of a user or a cat, such that the cat can defecate easily without stress. An outlet, through which the excrement is discharged, can be opened or closed by an opening/closing panel, and thus, it is possible to quickly block odor generated from the excrement collected in an excrement collecting box, thereby preventing the odor from spreading to an inner space in which the device of treating excretion of a cat is installed.본 발명에 의한 고양이 배변 처리장치에 관한 것으로, 고양이 배변 처리장치는 어퍼케이스와 로우케이스가 결합하여 전면에 고양이가 출입하는 입구를 형성하는 케이스와； 모터의 구동력에 의해 회전하면서 고양이의 배설물과 모래를 포함하는 배변처리물질을 분리할 수 있도록 케이스 내측에 경사지게 설치되는 드럼과； 고양이의 배설물과 배변처리물질을 분리하여 배출시킬 수 있도록 드럼의 내측에 회전 가능하게 설치되는 샌드필터와； 모터브라켓에 의
