The coix seed oil bilayer emulsion was prepared by chitosan oligosaccharide（CO） and whey protein isolate （WPI） which were cross-linked by glutamine transaminase. In vitro release of the bilayer emulsions was investigated using the simulative gastric and intestinal fluid. The results showed that both the bilayer emulsion using CO as an inner layer （mCO ∶ mWPI=1 ∶ 4） and WPI as an inner layer （mCO ∶ mWPI=1 ∶ 5） exhibited higher stability than that of the coix seed oil emulsion stabilized by WPI alone. In vitro release kinetics of both CO/WPI and WPI/CO bilayer emulsions fit well with Retger-peppas equation in the simulative intestinal fluid， of which the diffusion index was below 0.43， indicating that the release mechanism was due to the combination of Fickian diffusion and erosion control.