Abstract: Sea urchin gonad, as the only edible part of sea urchin, is rich in nutrients and phospholipids. Due to the high content of polyunsaturated fatty acids in phospholipids, lipid hydrolysis and oxidation reactions may happen during the storage and transportation, which will affect the quality and flavor of sea urchin gonad. In this study, phospholipids changes of sea urchin gonad was studied during 4 ℃ storage. The lipid composition of sea urchin gonad was analyzed by column chromatography. It was found that the phospholipids content decreased from 46% to 29% with the prolongation of storage time. The composition of phospholipids were measured by evaporative light scattering detector. The results showed that sea urchin gonad mainly contained phosphatidylethanolamine, phosphatidylcholine and phosphatidylinosidol during storage at 4 ℃. The content of phosphatidylethanolamine and phosphatidylinosidol decreased gradually, while the content of phosphatidylcholine firstly increased and then declined, and lysolecithin appeared after 48 h. The phospholipid fatty acid composition were determined by gas chromatography, and it was found that there were more than 20 kinds of fatty acids in sea urchin adenosine, and the unsaturated fatty acid/saturated fatty acid gradually decreased from 5.33% to 4.33% during storage. Hydrolysis and oxidation of phospholipids were found in sea gonads urchins during storage. Phospholipids changes of sea urchin gonad during cold storage were preliminarily summarized, and the theoretical basis for the quality change of sea urchin at storage was provided.