Tilapia scale gelatin was used as wall material,corn oil was mobile phase,sorbitan tristearate(Span 65) was emulsifier,ultrasonic technology was applied to prepare ascorbic acid microcapsules.The effects of emulsion,mobile phase,and ratio of gelatin and ascorbic acid were discussed.The results showed that the best parameters were: 1mL mixed solution at the mass ratio 15mg / mL gelatin and ascorbic acid with 2∶ 1,100 μL emulsion,20 mL corn oil,0.12 g / mL transglutaminase react at 40 ℃ for 7 hours.Under the above condition,the obtained microcapsules had an average particle diameter of 3.57 μm.The encapsulation efficiency was 89.78%,higher than mammalian gelatin encapsulate of 57.3%.This indicated that fish scale gelatin can replace mammalian gelatin.