The present invention discloses an oolong tea beverage preparation method and the oolong tea beverage is prepared by the following processing processes: weighing 1 g of glucose, 2 g of yeast extract, 1 g of soybean peptone, and 0.1 g of potassium dihydrogen phosphate, adding water to stir and dissolve the mixture to a constant volume of 100 ml, dampness-heat sterilizing the mixture at 121 DEG C for 15-20 minutes, then cooling the mixture to 70 DEG C, using a sterile pipette to add 3 ml of 95% edible ethanol, stirring evenly to obtain an acetic acid bacterium liquid medium, inoculating a ring of acetic acid bacterium from a slant into the liquid medium, conducting shaking culture for 36 hours at 28-30 DEG C and 150 rpm to obtain an acetic acid bacterium seed liquid, and filtering, diluting, blending, bottling, and sterilizing the mixed liquid to obtain the finished products. The oolong tea beverage preparation method well retains the original nutrients in the oolong tea, at the same time, increases many health-care factors and functional factors due to the fermentation function of yeast and acetic acid bacteria, improves the quality further, and also increases dietary fiber and other nutrients after tea residue is extracted by acetic acid. Regular consumption of the oolong tea can play a good role in health care for human body.