Twenty strains of Cryptococcus neoformans isolated from environmental and clinical sources in Korea were examined for their serotypes. Two environmental isolates from pigeon excreta belonged to C. neoformans var. neoformans serotype A. Of the 18 isolates from clinical specimens, 17 belonged to C. neoformans var. neoformans (serotype A : 16, serotype D : 1) and one belonged to C. neoformans var. gattii serotype B, which was culturally unusual, producing mucous colonies. This is the first report of the identification of C. neoformans var. gattii serotype B from a patient in Korea.