Abstract: Emulsion is difficult to get rid of the problem for the soybean aqueous enzymatic oil extraction process, based on single-factor experiments, three factors of NaCl concentration, salt, reaction time, the salt reaction temperature were chosen to evaluate in the present study. The response factor was oil extraction rate. By employing RSM design programmed, the optimized parameters were generated as follows:concentration of NaCl 5.6% , salt reaction temperature 93.5℃ , salt reaction time 16min and oil extraction rate 87.92% . The aqueous enzymatic extraction process of the formation of fat globules in the emulsion particle size distribution was observed by microscopic. The comparison found that the inorganic salt demulsification fat globule particle size increased significantly, grease easier to release.