The high-efficiency interception and filtration system of the internal inflow orifice plate grid consists of an orifice plate grid, a high drainage press, and a backwash system. It adopts a "two-dimensional filtration" method of middle inlet water and two sides outlet water. Through the interception of non-metallic orifice plates, hair fiber materials are intercepted and attached to the inner side of the orifice plate, achieving rapid and complete separation of solid and liquid, and purifying sewage. The backwash device will intercept the hair fibers on the inside of the orifice plate and flush them into the slag collection tank, allowing the orifice plate to achieve self-cleaning; The slag water containing hair fibers is transported to the press machine, where it is filtered and pressed. The slag enters the slag box, and the filtrate enters the orifice plate grid to achieve slag separation and dehydration.