Method for manufacturing a stiffened panel of composite materials and a stiffened panel, comprising:



a skin (1), and
stiffeners (3, 4),

wherein the manufacturing method comprises the following steps:

providing a skin (1),
making a plurality of through drill holes (6) on the skin (1) located in correspondence with areas where the placement of stiffeners (3, 4) is expected,
introducing threaded bolts (5) in the through drill holes (6) such that the head (11) of the threaded bolt (5) remains housed in the skin (1),
locating a threaded nut (10) on the free end of the threaded bolts (5),
manufacturing the stiffeners (3, 4) such that the threaded bolts (5) and the threaded nut (10) remain embedded in the stiffeners (3, 4).