Abstract: In this paper the characters of three kinds of oil extracted from eel bone by the method of enzyme hydrolysis were studied by the author. One of them is obtained in beating the bone in hot water. The second one is obtained in the enzyme hydrolysis. The third one is from the byproduct of the enzyme hydrolysis. All of the oils were deal with transesterification and winterization. The result shows that the characters of these lipids exist the most outstanding difference. The quality of eel bone oil obtained in enzyme hydrolysis is the best. The quality of the oil obtained by heating in hot water is poor. The amount of the oil get from the enzyme hydrolysis is about 50% of the total amount, and that one get from heating in hot water is 33%. The unsaturated degree of oil from eel bone was markedly increased by transesterification and winterization. Moreover, POV is enhanced to a great extent while oxygen exists.