The structure, thermodynamic, and kinetic features of polyunsaturated fatty acids derivatives as the main substratum of lipid peroxidation (POL) have been considered. The heats of key POL reactions have been estimated. Kinetic consequences of these estimations have been analyzed. The dependence of POL rate on O2 concentration have been considered in detail both in the absence and in the presence of antioxidants. The essential features of POL processes in lipid bilayers resulting from the specific structure and molecular dynamics have been discussed