The paper shows composition and content of phenolic compounds in leaves of 4 Nitraria L. species from 58 populations of Russia, Kazakhstan, and Tajikistan studied with high-performance liquid chromatography(HPLC). The investigation has revealed 27 compounds of phenolic nature: the maximum number (18 components) is detected in leaves of N. sibirica Pall. from Kazakhstan (the Karatal river valley), 16-17 components – in plants from three populations of Siberia, the minimum (6 components) – in leaves of N. komaroviiilljin & Lava ex Bobrov. The analysis has identified hyperoside (quercetin O-glycoside), narcissin (isoramnetin O-glycoside), quercetin (flavonol) and luteolin (flavon). The studied plants accumulate a generous quantity of phenolic compounds. Their content reaches 4.64% in leaves of N. sibirica, 3.11% – in N. schoberi L., up to 3.96% – in N. komarovii. The research results allow speaking about the species-specific composition and content of phenolic compounds of N. sibirica, N. schoberi and N. komarovii. The component composition is weaker in extracts of N. komarovii leaves, but there is a higher content of total phenolic compounds compared to N. schoberi plants. N. pamirica L. Vassil sample is close to N. schoberi on multidimensional analysis of the phenolic compound composition and content.