Disclosed are an excrement screening device and method. The excrement screening device includes a rotary receiving piece, a litter blocking piece and a screening piece. The rotary receiving piece is configured to receive cat litter and the rotary receiving piece is provided with a waste discharge outlet. The litter blocking piece is disposed in the rotary receiving piece and the litter blocking piece is configured to block the cat litter in a case where the rotary receiving piece rotates along a first direction. The screening piece is disposed in the rotary receiving piece, the screening piece is provided with a plurality of screening holes, and an accommodating cavity is formed by the screening piece, the litter blocking piece and the rotary receiving piece. The excrement screening method uses the above-mentioned excrement screening device.