Abstract: What is disclosed is a roller screen intended for being mounted on the frame of a window opening, a door opening or the like, which roller screen comprises a gauze screen, a roll-up mechanism for said gauze screen, which is accommodated in a housing, a pull beam connected to the free end of said gauze screen, and guides for guiding said pull beam and the side edges of said gauze screen. The guides each consist of a substantially cylindrical outer housing, which can be fixed to the frame, and a likewise substantially cylindrical inner housing, which is accommodated in said outer housing in such manner as to be concentrically rotatable therein. The outer housing and the inner housing are each provided with a longitudinal slot which extends substantially along their entire length, wherein the longitudinal slots of the outer housing and that of the inner housing overlap, seen in their circumferential direction, in an operative position of the roller screen.