Citrus juice, a concentrate manufactured by the Jeju Provincial Corporation, was convened into vinegar orderly by alcohol and acetate fermentation. The juice with a 6-fold dilution by distilled water was used as the sole nutrient source throughout fl-re experiments. The diluted juice contained 12.96Bix of total sugar;. 0.632% of total acid and 20.23 ㎍/㎖ of hesperidin.Naringin was not detected from the juice. Citrus wine having 5.6~6.3% alcohol was produced from the diluted juice after 3 clays of fermentation at 28℃. A kind of citrus-malomelo-yeast CMY-28 was used for the wine fermentation. The wine was successfully fermented for 8 days at 30℃ after inoculation of seed vinegar which contained active cells of acid producing bacteria M. The inoculum size of the seed vinegar was controlled to 10%(v/v) of the citrus wine. The wine was converted into vinegar by the fermentation process. Citrus vinegar, the final fermentation product, was colored with very thin, radish-yellow and was transparent. It`s acidity ranged between 5.8~6.2% of that of acetic acid. The vinegar attained the best score by sensory test among several natural fruit vinegars. It was clear from the results that high quality citrus vinegar could be produced from concentrated citrus juice. However, the fermentation conditions should be improved to reduce the amount of reducing alcohol.