The sunscreen/cosmetic composition as defined by claim 4, said at least one hydrophilic acid compound (i) having the following formula (II): ##STR13## in which R2 is a hydrogen atom, a halogen atom, an alkyl radical having from 1 to 4 carbon atoms or an --SO3 H radical, R3 and R4 are each a hydrogen atom or an --SO3 H radical, at least one said radicals R2, R3 or R4 being an --SO3 H radical, with