The invention discloses a cylindrical filter for filtering water of a granulator, which mainly comprises a cylindrical shell, a cover on the shell and a cylindrical filter element in the cylindrical shell, wherein the cylindrical shell is provided with a water inlet and a water outlet with the same height; the upper part of the cylindrical filter element is provided with a filter net cover capable of spreading; the upper end face of the cylindrical filter element is provided with a ring of which the circumference is provided with leak holes; the ring is contacted and matched with the cylindrical inner wall of the cylindrical shell; the ring is provided with a limit block; the inner wall of the cylindrical shell is provided with a limit groove penetrating to the upper end face and matched with the limit block; the cylindrical filter element is provided with a horizontal water inlet pipe opposite to the water inlet; and the water inlet end of the water inlet pipe has an arc surface contacted and matched with the inner wall at the water inlet, and the pipe diameter of the water inlet pipe is greater than that of the water inlet. The cylindrical filter for filtering the water of the granulator can ensure that liquid to be filtered enters the cylindrical filter element so as to ensure filtering effect.