Abstract: Structure intended to stiffen a component made of thermosetting composite material by being fitted to at least one of its surfaces, including: at least one longitudinal body, with first and second longitudinal edge faces on opposite sides, and first and second lateral faces on opposite sides; at least one base including at least one mounting base, each base having a plate and first and second tongues which delimit, with the plate, a housing for at least one body, the first and second tongues extending from a main face of the plate and being pressed respectively against the first and second lateral faces of the body. Each mounting base has a plate which is secured to the first longitudinal edge face of a body and which is intended to be pressed against the surface of the component to be stiffened. Each body and each base are made of thermosetting composite material.