This study was conducted to investigate habitat characteristics and growing environments of Japanese Aucuba (Cornaceae), which is one of most important ornamental tree species in Korea. Japanese Acucuba was distributed to Ulleungdo, Oeyeondo, Wido, Heuksando, Jejudo and Dangsado where are the limited island areas of the Korean peninsula. Natural habitats were located in moist valley and rocky areas at altitudes of 10~535m. One hundred and sixty three vascular plant taxa were identified from 9 sites in the six islands. Dominant tree species of the tree layer based on the highest importance values were Celtis sinensis, Machilus thunbergii, Quercus acuta and Cinnamomum japonicum, while in the subtree layer were Camellia japonica, Neolitsea sericea, Acer palmatum, Aucuba japonica and Orixa japonica, and in shrub layer were Eurya japonica. Average species diversity and evenness were 1.45 and 0.85, respectively.