The invention belongs to the technical field of deep processing and modification of oil, and particularly discloses a method for preparing glyceride rich in EPA and DHA through enzyme catalysis .Fish oil rich in EPA and DHA is used as the raw material, efficient selective catalysis of fish oil hydrolysis is conducted with lipase, and glyceride rich in EPA and DHA is obtained through molecular distillation separation purification by strictly controlling hydrolysis conditions including enzyme adding amount, pH, water-oil ratio, temperature and time .To increase the utilization rate of raw materials, EPA and DHA in a free fatty acid product obtained through molecular distillation are recovered with the urea coating method, so that transesterification can be conducted between EPA and DHA subjected to ethyl esterification and glyceride obtained through molecular distillation and rich in EPA and DHA, and the content of triacylglycerol, the content of EPA and the content of DHA in glyceride are further increased .The content of EPA and the content of DHA in triacylglycerol type fish oil obtained with the method can be increased by 25% and 15% or more respectively.