Physicochemical properties and the conditions of cold storage of kiyomi clangor(Citrus unshiu x sinensis) produced in Cheju were investigated. Firmness, edible part ratio, soluble solids, and acid content were decreased gradually with incurasing fruit size. Carbohydrates in juice were consisted of 65.12% sucrose, 19.65% fructose, and 15.23% glucose The main organic acrid In juice was 57.4% of citric acid, and others were lactic acid, malic acid, oxalic acid and fumaric acid, respectively. Weight loss were occured very. slowly to about 6% till late of May, but decayed fruits were occurred very slowly to about 6% till late of May, but decayed fruits were arisen to about 8% at 3$^{circ}C$, and about 13% at 5$^{circ}C$ of storage temperature. The changes of peel moisture content, soluble solids, total sugar, vitaamin C, and density of fruits were slightly occured during cold storage. Cold storage at 3$^{circ}C$ and 87% relative humidity kept freshness of citrus fruits for a long-term without damage of cold injury.