Taking raisins as the raw materials, the effects of different fermentation parameters impact on natural yeast fermentation of the grapes were studied. The single factor experiment and response surface analysis were used to optimize the fermentation technological conditions. Results: The optimum condition was obtained by response surface optimization as follows: the temperature of 26 ℃, train number 4 days, ratio of raisins and granulated sugar 10︰1.Under this conditions, the natural yeast fermentation of the grapes reached 0.077 9, closed to the fermentation of dry yeast, and can be used in the production of bread.