A method for repairing a sound attenuation panel is disclosed. The panel includes a structuring skin in metal material, a resistive layer in metal material and a honeycomb structure as acoustic absorption material directly added onto the structuring skin and resistive layer. The method includes a step in which one reinforcing pin is inserted into the thickness of the attenuation panel and a step in which the reinforcing pin is secured by welding in a controlled atmosphere to the structuring skin and resistive layer respectively.