Cosmetic use of at least one micro-organism of genus Bifidobacteriumspecies, one of its fractions and/or one of its metabolites to prevent and/or treat a skin disorder in a sensitive skin, where the microorganism is implemented in the form of a lysate, is claimed. An independent claim is included for a cosmetic and/or dermatological composition, to prevent and/or treat the skin disorder in the sensitive skin, comprising the lysate of at least the micro-organism of the genus Bifidobacteriumspecies in combination with at least one compound able to cause skin irritation, in a medium. ACTIVITY : Dermatological. MECHANISM OF ACTION : None given.La présente invention concerne l'utilisation cosmétique d'une quantité efficace d'au moins un lysat d'au moins un microorganisme du genre Bifidobacterium species et/ou fraction de celui-ci pour prévenir et/ou traiter un trouble cutané au niveau d'une peau sensible.