The invention relates to a grass cutting device, in particular to a grass cutting device used in animal husbandry. The technical problem to be solved by the invention is to provide the grass cutting device used in animal husbandry, which can perform air drying on cut grass in time, cuts grass uniformly and can separate grass cuttings with the grass. In order to solve the technical problem, the grass cutting device used in animal husbandry comprises a base plate, a 7-shaped rack, a collecting frame, a first belt pulley, a small cam, a cutting box, a screen, a push plate, a fan, a guide rod, a guide sleeve, a connecting rod, a sliding rail, a sliding block, a first spring, a cylinder, a fixed seat, an elastic piece, an oscillating rod, a first baffle block, a connection rod, a blade, a motor, a large flat belt, a fourth belt pulley and the like, wherein the first belt pulley and the 7-shaped rack are arranged on the base plate. According to the grass cutting device used in animal husbandry, by using the manner that the up-and-down motion of the blade works together with the up-and-down motion of the screen, the grass on the screen is uniformly cut, and the grass cuttings fall into the bottom inside the cutting box through the screen.