The invention relates to machine a component made of composite material in order to eliminate singularities, defects or damage to the component using a method that is repeatable and adaptable. To do this, it is proposed that the defects and their type be identified by image processing of the surface of the component and that the local machining rates at which the plies are machined be regulated at the function of this identification. According to one embodiment, a system (10) for the ply-by-ply machining of defects of a component made of composite material includes a numerical data processing unit (1) combined with a sweep control (2) that commands the sweep of a high-pressure water jet machine (20), and an image formation assembly (3) including an image capturing device (30, 31) connected with the numerical processing unit (1). The processing unit (1) includes regulating devices (11, 13) indexing local sweep rates, by convergence of brightness levels (NB) from the successive sweeps, these being formed by the image capturing assembly (3) toward making the brightness uniform according to a model (Mr) correlating brightness to ply state typology identification (BT) that can be supplied by a library (4). The correlation data (BT) and brightness levels (NB) are stored in memory modules (12, 14) of the processing unit (1).