The utility model discloses a paper cutting device. The paper cutting device comprises a base, a base board, a rotating arm, paper cutting moulds and a positioning strip, wherein the base board is arranged on the base; the rotating arm is arranged on the base through a rotating shaft; one ends of the paper cutting moulds are fixedly connected with the rotating arm; each paper cutting mould is provided with a first cutter, a second cutter and a third cutter; a first gap for accommodating the paper cutting moulds is formed in the positioning strip; rectangles formed by the positioning strip, the first cutters, the second cutters and the third cutters are the same as cut paper in shape; a second gap the same as the cut paper in shape is formed in the base board; the first gap corresponds to the second gap in position. During use, a user puts paper to be cut in the base, ensures that one edge of the paper is propped against the positioning strip, and then rotates the rotating arm; the paper cutting moulds fall on the base board with the rotation of the rotating arm to cut the paper. As the rectangles formed by the first cutters, the second cutters and the third cutters are the same as the cut paper in shape, so that paper cutting can be completed through one step, and the cutting efficiency is improved.