The qualitatively important components of green tea (theanine, caffeine, ascorbic acid, (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin gallate and (-)-epigallocatechin gallate) were analyzed simultaneously by using capillary electrophoresis. The running buffer used was borate buffer (80 mM, pH 8.4) containing 50 mM of sodium dodecylsulfate. The extracts of green tea, oolong tea and black tea were analyzed using this method. Green teas of different plucking dates and the leaf samples from different positions in one shoot were also measured using this method. These results showed that this method will considerably save time and labor for the analysis of these components, and is quite useful for the quality estimation of teas (particularly of green tea) and characterization of fresh tea leaves.