The effect of the steroid plant hormone 24-epibrassinolide on the content and composition of complex oxylipins in plants was studied for the first time, using flax as a model plant. In plants treated with the plant hormone, as well as in plants inoculated with Pectobacterium atrosepticum, the content of linolipins (galactolipids containing divinyl ether residues) increased. Hormonal pretreatment of the plants with subsequent infection resulted in a more significant accumulation of linolipins B (21-fold) and A (2.8-fold) as compared to the untreated (control) plants. The data suggest that brassinosteroids are involved in the regulation of the formation of complex oxylipins in pathogenesis of plants.