Methanol extract of plants in Jeju were investigated for biological properties related to whitening cosmeceuticals such as melanin contents on melanoma cell, mushroom tyrosinase activity inhibition. We found that extracts of leaves of Hypochoeris radicata, Solanum nigrum, Solidago serotica Gynostenmma pentaphyllum and Taxus cuspidata inhibit melanin synthesis in B16F10 melanoma cells. However they have no tyrosinase inhibitory activity.