Total carbohydrates of Kumquats was 14.69% Kumquats, Citrus natsudaidai, and C. platgmama contained 18.3, 11.1 and 13.0%, of soluble solids, and 42.39, 32.09 and 20.13mg/100g, of vitamin C, respectively. Acid contents of C. natsudaidai and C. plafmama harvested on March 1995 in south Cheju were 2.52% and 0.89% . In preparing of Kumquats-tea, combination of 50% honey and sugar, 5% oligo-sugar, 32% Kumquats slice, 13% juice of C. natsudaidai were the best recipe for sensory evaluation. In C. natsudaidai-tea, combination of 5∼10% peel slice treated at 90$^{circ}C$ for 1min, 50∼60% concentration of sugar and 35∼40% of flesh of C. natsudaidai were good. for sensory evaluation. Microbial growth was not observed in the sterilized products for more than one month at 30$^{circ}C$.