The article presents the results of the study of raw materials (sugar, starch) and biologically active substances (pectin substances, catechins, saponins, flavonols, ascorbic acid) in the leaves and rhizomes of Hemerocallis hybrida plants of the Speak to me variety during seasonal development during 2013–2015. The quantitative content of the main groups of substances in underground and aboveground organs during vegetation, flowering and fruiting was determined.