The article presents a study that investigates the role of lipids in the adaptation of White Sea mussels Mytilus edulis L. to changes in water temperature. The study used thin layer chromatography (TLC), high performance liquid chromatography (HPLC), and gas-liquid chromatography to investigate total lipids, individual phospholipid fractions, and fatty acid profile of phospholipids in the mussels. Moreover, the study was supported by the Russian Foundation for Basic Research.