A linear gas burner for the heat treatment of webs of material has at least one feed line for fuel gas and a long, hollow body, in one of the long sides of which a series of burner nozzles is provided. To equalize the length of the flames and to avoid useless excess lengths or burner at the two sides of the material webs, the hollow body is divided in its longitudinal direction by a baffle into a low-pressure space and a high-pressure space, into which the feed line for the fuel gas opens. The baffle has openings for the passage of the fuel gas, which flows into the low-pressures space in front of the burner nozzles. To simplify production and to reduce production and assembly costs, the hollow body consists of a continuous, extruded metal profile with an essentially U-shaped cross section with a yoke part and two sidepieces, between the free ends of which at least one nozzle plate with two long edges and the burner nozzles is inserted, the sidepieces being clamped by tension rods against the nozzle plate or plates. Preferably, a hole structure for the further equalization of the flow is provided between the baffle and the burner nozzles.