Content of total phospholipids and their individual fractions, studied in rat brain grey and white substances during postmortal autolysis, was distinctly and dissimilarly altered in these tissues and the rate of alterations depended on time of incubation. Relative content of phosphatidyl serines + sphingomyelins, phosphatidic acids + polyglycerophosphatides in grey substance as well as of phosphatidylinositides, phosphatidic acids + polyglycerophosphatides in white substance were increased, while phosphatidylinosidtides in grey substance and phosphatidyl serines + sphingomyelins in white substance were decreased within later (4 and 24 hrs) periods of autolysis. Content of phosphatidyl cholines, phosphatidyl ethanolamines, glycerophosphates and lysophospholipids was also dissimilarly altered in brain grey and white substances both within early and later periods of autolysis. The schemes of metabolic interrelations between phospholipids of rat brain grey and white substances during autolysis are considered involving hydrolase, transferase and other reactions of lipids biotransformation. This multiple complex of biochemical reactions may be among the reasons responsible for dissimilar and time-dependent deteriorations of individual brain structures after death.