The report presents the results of the study of the chemical composition of nettle herb, 40%, 70% extracts, and extracts of polyphenolic complexes (PPC). Nettle herb were collected by the authors in June-July 2007–2020 in the territories of Tomsk, Kemerovo, Kursk, Novosibirsk, Moscow, Kirov, Tver regions, Altai and Krasnoyarsk Krai; Altai Republic. Extracts, polyphenolic and polysaccharide complexes were obtained from the herb. The studies was conducted using PC, TLC, UV-spectroscopy, HPLC, titrimetry, neutron activation. Reverse-phase HPLC were carried out on a chromatograph «Dionex Ultimate 3000» with UV-detector in the wave length range from 254 to 330 nm. Separation was performed by a column with reversed-phase sorbent «Restek Pinnacle IIC18» (150×4.6 mm, particle size 5 µm), flow rate of mobile phase is 1 ml/min; temperature is 20 °C, mobile phase (50 ml of acetonitrile, 50 ml of 0.1% trifluoroacetic acid) were carried out on. The study showed that nettle herb, 40%, 70% extracts and PPC contain phenolic compounds: phenolcarbonic acids, flavonoids, catechins, tannins; vitamin C and pigments. Baicalein, chrysoeriol, scutellarin identified for the first time. One of the dominant groups is hydroxycinnamic acids. The composition of flavonoids, phenolic carboxylic acids, catechins, hydroxycinnamic acids, including chlorogenic acid, chlorophyll, the sum of phenolic compounds, catechins are similar in 70% extract and its PPC. Additional information was obtained on the elements contained in nettle herb and its extracts.