Abstract: Fermentation technology of EPS produced by Streptococcu.cremoris was studied through single factor and rthogonal experiment. During single factor test, the influence of different factors on EPS yield was analysized as different carbon sources, different lactose contents, different initial pH, different cultivation temperature, different mineral quantity, and different fermentation time. Orthogonal experiment was carried by combining the three factors, lactose contents, initial pH and inoculums under three different levels. The best fermentation technology was obtained as lactose content 20 g/L, initial cultivation pH5.5, inoculum quantity 5.0％, fermentation temperature 37℃，fermentation time 24h, the most yield being 499.81mg/L.