Genistein (4',5,7-trihydroxyisophlavone) is found in representatives of the family Fabaceae and plays an important role in the regulation of plant cells. Genistein shows a wide range of biological activity in vivo and in vitro experiments: estrogenic, anticancer, antidiabetic, immunostimulating, antioxidant, radioprotective. The aim of the work was to modernize and study in more detail the chemical synthesis of genistein using the "deoxybenzoin" scheme. In the Houben-Höesch reaction between phloroglucinol and (4-hydroxyphenyl)acetonitrile, the diethyl ether can be substituted for the less flammable 1,4-dioxane with increased yield. As a catalyst for this reaction, instead of zinc (II) chloride, it is more convenient to use boron trifluoride etherate in the proportion 0.5 mol/mol of genistein. The study of the products of the reaction of deoxybenzoin with the Vilsmeier reagent showed that in the absence of boron trifluoride etherate, the reaction proceeds non-selectively and a mixture of genistein, 6-formyl- and 8-formylgenistein is formed. Increasing excess boron trifruoride etherate leads to substantial increase in genistein yield. The obtained results can be used in the production and quality control of the pharmaceutical substance genistein.