Abstract: Yinghong No.9 black tea was chosen as test material for investigation of the color, pH, electrical conductivity and main quality components of tea infusion when five types water （ultra pure water, tap water, natural mountain spring water, natural mineral water, purified water） were applied. Through correlation analysis, the effects of different water quality on the color and quality components of Yinghong No.9 black tea soup were studied. The results showed that pH, conductivity and soluble solids content of water samples increased, brightness of tea infusion decreased and redness increased, different water quality had significant influence on the total catechins, especially ester catechin.

Key words: water quality, black tea, Yinghong No.9, quality, physicochemical composition