An acoustic treatment panel includes, from the inside to the outside, a reflective layer (50), at least one alveolar structure (52), and at least one acoustically resistive structure (54) that forms an aerodynamic surface, whereby the panel is connected at one edge to at least one second panel (46), characterized in that it includes, at the edge overlapping with the at least one second panel, a reinforcement (60) that is inserted between the reflective layer (50) and the acoustically resistive structure (54) forming the aerodynamic surface, whereby the reinforcement (60) ensures the uptake of forces between the layer (50) and the structure (54).