The invention relates to a method for preventing and/or treating skin disorders related to Propionibacterium acnes, comprising a step consisting in applying, to acneic skin, a dermatological composition comprising, in a physiologically acceptable medium, at least one anionic surfactant in an amount ranging from 0.001% to 0.05% by weight, relative to the total weight of the composition, and a step consisting in applying, to the treated skin, light radiation having a wavelength of between 360 and 450 nm, for at least 3 minutes.