The factors influencing the existence of lichens in the ice-free areas along the Soya Coast and Prince Olav Coast, Antarctica are discussed. Water supply is one of major factors. Lichens grow luxuriantly in the sites where an adequate moisture is maintained due to snow and ice brought by the "katabatic wind" through the surface of ice cap, while lichens are absent or poorly developed in the dry sites which are buffeted by cyclonic wind through the surface of sea ice. Moisture for lichens appears to be supplied not only from snow-melt water but also from air. The wind-blown sea spray is one of the unfavorable factors for lichens in the areas investigated. Well-developed lichens can be seen around the rookeries or nests of sea birds. However, they are absent around the rookeries which are influenced bv the wind-blown sea spray
