In order to study the correlation between tea quality and chemical composition, the concentrations of amino acids, purine alkaloids, catechins were determined by HPLC in four different grades of organic Maofeng tea from Hangzhou region (Special grade, Grade 1, Grade 2, Grade 3), together with their sensory evaluation. Results indicated that tea quality grade reduced as the content of amino acids and purine alkaloids decreasing. The amount of catechins decreased with the tea quality grade except that the concentration of catechins in the Special grade was slightly lower than that of Grade 1. Moreover, the ratio of the content of catechins to total amino acids increased with quality grade dropping. Therefore, this Maofeng tea showed a positive correlation between the quality grades and chemical compositions in the view of the sensory evaluation factors as tea appearance, aroma, taste, liquor color and infusion.