The invention relates to a device for fixing at least one plastic film on the framework of a greenhouse roof by wedging said at least one plastic film between a rail secured to the frame and an intermediate section, and maintaining the intermediate profile in the rail by means of a locking profile. According to the invention, the fixing device comprises a first compression roller and a second compression roller capable of rolling on the rail. The first and second compression rollers acting, during the displacement of the fastening device along said rail, respectively on the intermediate profile to fit into the rail in order to wedge said at least one plastic film between the rail and the intermediate profile , and on the locking profile for the clipper in the intermediate profile to maintain in position the intermediate profile in the rail.
