Abstract: Using methanol to induce the expression of Aspergillus niger glucose oxidase gene cloned in Pichia pastoris GS115 mut^{+ was deeply investigated for establishing a high-performance but low-cost method of recombinant glucose oxidase production. The medium, the pH, the time point of induction, the temperature and the methanol concentration for induction were optimized and studied in detail by shake flask experiment. The results of optimization were verified by enlarged fermentation in 50 L fermentor. Results suggested that the best medium culturing the Pichia pastoris were YEPD medium, the optimum time for induction was the mid-anaphase of logarithmic phase, the optimum inducing concentration of methanol was 1%, and the optimum pH and temperature conditions were pH6-6.5 and 25℃. According to the optimum conditions, the highest biomass and glucose oxidase expression level were obtained in 50 L fermentor with batch culture for 14 h and induced by 1% methanol for 48 h. The final cell density（OD600­­­）was 44, 105 kU enzyme activity and 1 000 mg protein were obtained in 1 L fermentation broth.}