Abstract: Some embodiments of the present disclosure provide an automatic cat excrement removing device, including: a ball compartment assembly configured to have at least three spaces including a working compartment, a screening compartment, and an excrement collection compartment; and a driving assembly configured to drive the ball compartment assembly to rotate, wherein when the ball compartment assembly rotates to a first position, the screening compartment is located at the lowest position of the ball compartment assembly, so that the cat litter falls into the screening compartment through the screening holes, while the cat excrement stays in the working compartment because the size of the cat excrement is larger than that of the screening holes; and when the ball compartment assembly rotates to a second position, the excrement collection compartment is located at the lowest position of the ball compartment assembly, so that the cat excrement falls into the excrement collection compartment.