The invention discloses a method for prevention of porosity in composite material parts (1), which is applied when the curing stage of the part (1) is being carried out on a female tool (2). In the curing stage, an adhesive (4) is placed on at least one of the areas of the radii (5) of the composite material part (1), so that the possible subsequent appearance of porosity in said areas of the composite material part (1) is prevented. Thus, the adhesive (4) acquires the fluidization temperature before the resin of the composite material and it is displaced filling the holes generated during the placement of the part (1) on the female tool (2), in the area of the radii (5) of the part (1), during the coupling between the part (1) and the female tool (2).