The invention discloses a chain wheel circulating type horizontal pressing plate mechanism which comprises a first chain and a second chain which move synchronously and have the same movement track. Horizontal pressing plates are mounted on the opposite sides of chain links of the first chain and the second chain at the same position of the respective track, and in the movement process, the postures of the horizontal pressing plates are kept unchanged. The chain wheel circulating type horizontal pressing plate mechanism is simple in structure and easy to maintain; materials on a conveying belt can be discharged horizontally rapidly efficiently, and the chain wheel circulating type horizontal pressing plate mechanism is high in practicality and economy.