The utility model discloses a but autofilter prilling granulator, be equipped with the third flight on vertical rotary rod, the below of forcing the feeding hopper is equipped with the extrusion device, the extrusion device is including the extrusion wheel, one side of extrusion wheel is equipped with hydraulic telescopic device, extrusion device below is equipped with garrulous whole case, garrulous whole case below is equipped with filter equipment, be equipped with the rotary rod in the filter equipment, be equipped with the second flight on the rotary rod, the rotary rod below is equippedwith the tiny particle filter screen, tiny particle filter screen one side is equipped with the large granule filter screen, tiny particle filter screen below is equipped with the discharge gate, large granule filter screen below is equipped with conveyor, conveyor one end links to each other with hoisting device, the conveyor other end is equipped with the second rotating electrical machines, beequipped with the second belt on the rotatory motor output shaft. Beneficial effect: carry out automatic extrusion again through the screening to the great granule of granule, operating sequence is simple, and particle uniform is pollution -free, and is efficient.