This article through the design different buffer solution extraction peroxide enzyme, determines extracts best, uses the ammonium sulfate graduation precipitation method to carry on the preliminary depuration to the peroxide enzyme, uses not the continual polyacrylamide gelatin vertical board electrophoretic techniques and the benzidine dyeing again carries on the zymogram analysis to the peroxide enzyme, carries on the thermostability again to the peroxide enzyme and the most suitable PH research. The experimental result indicates in the sweet tea to include certain kind of peroxide enzyme, each peroxide zymogram has 1-2 enzyme belts, the peroxide enzyme when 50℃-60℃ activeness is best, elevates or reduces activeness along with the temperature to reduce gradually, the peroxide enzyme's most suitable pH scope is 5.5-7.5.