A system is disclosed for attaching a cap of composite material to the exhaust housing of a turbojet. The system consists of three triangular rod assemblies arranged between the housing and the cap. The triangular rod assemblies bear at their ends eyelets pivotally connected to brackets attached to the housing. The connecting rods are connected to the brackets by means of pivot pins, and to the cap by an attachment part and pivots. The attachment part is fixed to the cap by a bolt. The housing and the cap have cooperating bearing surfaces as well as a seal device.