Abstract: In order to demulsify the emulsion forming in the aqueous enzymatic extraction of oil from peanut and improve the free oil yield, the property of the emulsion was studied. The molecular weight distribution, the Polyacrylamide gel electrophoresis(PAGE) and reversed-phase high performance liquid chromatography(RP-HPLC) graphs of the peptide in aqueous phase and in interface were compared. The results indicated that the property of the interfacial peptide contributing to stability of emulsion were relative to its conformation, composition and electric charge. The rheological characteristics of the emulsion showed that the emulsion was a typical elasticity system, and the stability of emulsion could be reduced by improving the temperature and shear rate of the emulsion. Based on those results, the effects of four different demulsification methods were compared and the results showed the effect of the method of freezing and thawing combining with centrifugation was the best and the oil recovery was more than 91.6%. High-speed shearing couldn’t recover the oil from emulsion and it caused the emulsion to emulsify again.