A laminated composite structural panel with fiber reinforcement comprising a skin with a thickness e1 and a localized reinforcement or patch. The skin is made up of a stack of fibrous plies in a matrix made of a thermoplastic polymer. The localized reinforcement or patch is joined to the surface of the skin and rises to a thickness of e2 in a direction that is locally normal to the skin, which is made up of a stack of fibrous plies in a matrix made of thermoplastic polymer. The surface of the plies that make up the patch is decreasing from the ply of the patch in contact with the skin so that the edges of the patch have a slope p greater than 0.5. The patch and the skin is joined by a weld.