Three methods of total chlorogenic acid determination in green coffee were studied. Six coffee samples, three Soft (best) and three Rio (worst) were used. The method of MOORES et al. (1948), WEISS (1957) and GNAGY (1961, 1962) adapted by AMORIM (1972) gave no statistic difference when Rio coffees were used, however, the method of MOORES et al. (1948) and WEISS (1957) gave lower values than the GNAGY - AMORIM procedure, for the Solft coffees. No statistical difference was found between MOORES and WEISS methods. It was infered that the higher enzymatic activities of polyphenol oxidase found in the best coffees (Solft), oxidize the chlorogenic acids in the extraction procedure of the MOORES and WEISS methods, leading to the lower chlorogenic acid values observed.