Abstract: The research analyzed the changes in organoleptic quality and chemical composition of Mengdinghuangya during processing using the tea samples of Mengdinghuangya as objects. The results showed that the content of amino acid,soluble protein and soluble sugar were firstly increased and then decreased in the whole process; the content of catechins, caffeine, tea polyphenols, chlorophyll a and chlorophyll b were decreased gradually with the process. And the content of chlorophyll a and chlorophyll b reduced amplitude was larger,respectively 52% and 44.44%. The content of the water extract and tea pigment increased gradually with the process. The content of the thearubigins and theaflavins increase amplitude was larger,respectively was 56.52%,54.55%. As could be seen from the organoleptic evaluation,the quality characteristics of the tea sample of the third-fried were closed to Mengdinghuangya. So it showed that the unique quality characteristics of Mengdinghuangya had been preliminarily formed after the heaping for yellowing.