The purpose of this study was to (md out the characteristics of the residential house in Ulleung Island in terms of building materials, structure and construction method, structural design by actual field surveys. This study found several facts; First, the house was classified into the log house and mud-wall house according to building material for wall structure. The log house prevailed in the early days of the settlement in the island because of affulent timber materials available around. However, the mud wall house became a popular type in later days because of the depletion of timber materials. Second, the Udeki wall was an unique installation reflecting the severe climate conditions of Ulleung Island. However, many aspects of the Udeki wall was changed according to the change of living style and the introduction of modem heating systems in terms of its function, size, building material, layout position etc. Third, the roofing material also has been changed from materials available locally to slate materials transported from the mainland. Fourth, the bamboo slender-ribbed door as a single-swing door type was popular and later time the single-sliding door or three ribbed door was widely used in rooms installed later instead. Fifth, the roof was placed over the room, kitchen, and Chukdam (outer wall) and this was a resonable way to cope with heavy snowfalls in the winter season in Ulleung Island.