Abstract: A method for simultaneous analysis of theanine and gallic acid was established by HPLC technique . The content variations of theanine and gallic acid of solar dried green tea of Camellia sinensis var. assamica and its producing Pu-Er tea were determined by this method . The results showed that the contents of gallic acid significantly enhanced and theanine distinctly reduced in Pu-Er tea . It is noticed that the content of both of theanine and gallic acid are correlative with the producing place and quality of crude materials, as well as with the producing process of the post-fermentation of Pu-Er tea . The mechanism of content variation of theanine and gallic acid was discussed primarily .

Key words: Pu-Er tea