The present invention provides a method for extracting a lipid mixture having a high percentage of phospholipids comprising polyunsaturated fatty acids. The method comprises the steps of (a) heating the viscera of fish with hot water or steam; and (b) extracting from the heated viscera of fish, using a solvent, the lipid mixture containing phospholipids comprising polyunsaturated fatty acids. The lipid mixture obtained by the present method contains phosphatidylserine comprising docosahexaenoic acid and phosphatidylethanolamine comprising docosahexaenoic acid in high concentration.