Introduction. Sowing rye (Secale cereale L.) and common barley (Hordéum vulgáre L.) are annual herbaceous plants of the Poaceae family, they are widely cultivated in many countries around the world as cereals and fodder crops. Sufficient raw material base of sowing rye and barley makes them promising sources for new drugs. Materials and methods. The fatty acid composition in lipophilic fractions of seeds, stems and leaves of sowing (Khamarka variety) and common barley (Shedevr variety) was studied by gas chromatography. Results. As a result of the study, the quantitative content of 14 fatty acids in the stems and leaves of barley, 13 – in the leaves of rye and 12 – in the stems of rye and in both types of studied seeds was identified and established. In all types of the studied raw materials, unsaturated fatty acids were quantitatively predominant, the content of which prevailed in seeds of rye – 82.89 % and barley – 76.35 %. In stems of common barley their content was 64.04 %, leaves of common barley – 66.31 % of the amount. In stems and leaves of rye, the predominance of unsaturated fatty acids over saturated ones was insignificant: 49.00 % vs. 47.05 % and 53.70 % vs. 43.03 %, respectively. Among the unsaturated fatty acids, linoleic and linolenic acids dominated. Palmitic acid predominated among the saturated raw materials in all types of studied raw materials Conclusions. Quantitative content of fatty acids in seeds, stems and leaves of sowing rye (Khamarka variety) and common barley (Shedevr variety) was identified and established by gas chromatography. The results of the research indicate a rich fatty acid composition of the studied raw materials and can be used to create drugs based on them