In order to solve the problem of short shelf life of bread, this study developed a composite emulsifier to prevent corruption of bread and improve its quality. The effects of glycerol monolaurate, polyglycerol fatty acid ester and sodium stearyl lactate on the quality of bread and the inhibition of microbes were studied by response surface methodology. Experiments were designed using combination of single factor method and Box-Behnken design. The colony count, bread specific volume and bread hardness were used as the testing indexes by the response surface analysis. And the bread comprehensive score for the final index was used as the response value. The optimized formulation was with 0.75% polyglycerol fatty acid ester, 0.60% glycerol monolaurate and 0.15% stearoyl lactylate. By this formulation, the specific volume was 5.87 and the hardness was 474.4. Compared with the control group, the specific volume of bread was effectively improved 20% and the hardness of bread was decreased by 22%. It extended the shelf life of bread over four days at 30 ℃, 70% of the humidity. The quality was improved and the shelf life was extended significantly by the optimized formulation.