Racodium therryanum from Korea is described here for the first time. This fungus is characterized by that it is isolated from conifer seeds and seedlings, including Abies, colonies are dark green to dark gray and intricate, and it forms chlamydospores in cultures. This pathogenic fungus was isolated from seeds of Abies koreana growing on Mt. Halla, Jeju island. The fungus stopped growth more than at 30oC but grew even at 0oC. This fungus infected seeds of A. koreana under the snow during winter season. There is a high probability that this fungus affects the natural regeneration of A. koreana on Mt. Halla.