The content of biologically active phenolic compound (flavonoids, phenolic acids and tannins) in dry herb of E. angustifolium and E. hirsutum was determined. The herb was collected in the vegetative and generative stage. The content of the investigated compounds depended on the plant developed stage. The largest content of flavonoids and tannins was observed in the vegetative stage. The content of phenolic acids was higher in the generative stage of plant development. Qualitative analysis of flavonoids was performed by HPLC. The main flavonoid compounds in both species were rutin and luteolin-7-glucoside.