A melanogenesis inhibitor characterized by containing at least one kind of piperonyl alcohol represented by the following general formula (1) ##STR00001## wherein R is a straight chain or branched chain alkyl group having 3 to 18 carbon atoms, a straight chain or branched chain alkenyl group having 3 to 18 carbon atoms, or an optionally substituted alicyclic alkyl group.The melanogenesis inhibitor is superior in stability and safety and has a high melanogenesis-inhibiting effect; and a skin preparation containing the melanogenesis inhibitor is very stable, safe, and has a sufficient fair skin effect and a sufficient effect for curing skin dyspigmentation.