An apparatus serves for removing fine material to be screened from waste water. The apparatus includes a sieve grate (6) and a detaching device (16). The sieve grate (6) is cylindrical, and it is rotatingly driven. The sieve grate (6) allows for waste water to flow from its interior towards its exterior. The sieve grate (6) includes a supporting body (13) and a mesh sieve (7). The supporting body (13) is located at the exterior of the sieve grate (6). The supporting body (13) is made of a perforated sheet metal including comparatively large openings (37). The supporting body (13) provides for resistance and stability of the sieve grate (6). The mesh sieve (7) is located in the interior of the sieve grate (6). The mesh sieve (7) forms a separation surface (14) for the material to be screened. The mesh sieve (7) includes meshes of a comparatively small size. The mesh sieve (7) is fixedly connected to the supporting body (13). The detaching device (16) is arranged outside of the sieve grate (6). The detaching device (16) includes a plurality of nozzles (22). The nozzles (22) are designed and arranged to spray water from outside of the sieve grate (6) towards the interior of the sieve grate (6) in a way to detach material to be screened adhering to the inner surface of the sieve grate (6).