Composition (A) comprises at least one hydroxylated diphenyl-methane derivative (I) and at least one phenanthrenol compound, in a medium. Composition (A) comprises at least one hydroxylated diphenyl-methane derivative of formula (I) and at least one phenanthrenol compound in a medium. R1 : H, methyl, optionally saturated 2-4C alkyl chain, -OH or halo; R2 : H, methyl, or optionally saturated 2-5C alkyl chain; R3 : methyl or optionally saturated 2-5C alkyl chain; and R4, R5 : H, methyl, optionally saturated 2-5C alkyl chain, -OH or halo. An independent claim is included for a cosmetic or dermatological set comprising: a container delimiting at least one compartment, where the container is closed by a closure element; and the composition is placed inside the compartment. [Image] ACTIVITY : Antiseborrheic; Dermatological. MECHANISM OF ACTION : None given.