The present invention relates to a method for preparing a mixed fermented tea having improved taste and flavor by promoting the oxidation polymerization of catechin contained in third-harvest leaves of green tea by using one among jujube leaves, jujube tomato leaves, apple leaves, pear leaves, blueberry leaves, and burdock leaves. According to the method for preparing a mixed fermented tea, the washed green tea leaves, jujube leaves, jujube tomato leaves, apple leaves, pear leaves, blueberry leaves, and burdock leaves are respectively placed on drying trays, wilted at a temperature of 30-50°C to have a moisture content of 50-60%, and cut into sizes of 10-30 mm. Then, 10.0 wt% of one among jujube leaves, jujube tomato leaves, apple leaves, pear leaves, blueberry leaves, and burdock leaves is put in the third-harvest leaves of green tea within a grating machine, followed by mixing and grating for 10-40 minutes. After that, the resultant material is fermented for 0.5-2 hours in the conditions of a temperature of 20-30°C and a humidity of 70-90%, and then dried to have a moisture content of 3.0-5.0 wt% in a hot-air drier. The present invention is related to a mixed fermented tea and a method for preparing a mixed fermented tea powder, in which the fermented tea, prepared by using one among jujube leaves, jujube tomato leaves, apple leaves, pear leaves, blueberry leaves, and burdock leaves in the third-harvest leaves of green tea, has improved astringent taste and bitter taste since polyphenols are oxidized to generate theaflavins during a fermenting procedure, thereby providing fruit and floral aromas.COPYRIGHT KIPO 2014[Reference numerals] (AA) Wash green tea leaves (BB) Wilt the washed green tea leaves (CC) Cut the wilted green tea leaves (DD) Wash jujube leaves (EE) Wilt the washed jujube leaves (FF) Cut the wilted jujube leaves (GG) Mix and grate the cut green tea leaves and jujube leaves (HH) Prepare a mixed fermented tea of green tea leaves and jujube leaves
