Abstract: A housing for a coaxial directional coupler has a channel-section body (20), each of the flanges of said channel-section body having two openings (2) with the opening in each flange being opposite to the corresponding opening in the other flange. A cover (5) is capable of closing the open space between the rims of said housing body flanges, as well as two end pieces (8) for closing the ends of the assembly formed by the channel-section body of the housing (20) and the cover (5). The invention is used in strip lines, insertion boxes, attenuators, housings for micro-electronic equipement, hybrid circuits and the like.