The potential of phenolic compounds of medicinal plants including Astragalus danicus L is determined by but not limited to their antioxidant activity. Their anti-inflammatory, antitumor, and other useful properties are known, which allows using these phytochemicals within preventive activities to reduce the risk of many serious diseases. Chromatographic analysis of the Astragalus danicus L. biomaterial from the plant samples collected in three regions of the Kemerovo region (Western Siberia, Russia) established the presence of compounds of flavonols (isorhamnetin glucoside, kaempferol glucoside), flavones (apigenin 7-glucoside), phenylpropanoids (chlorogenic acid) in the aerial part of plants. The total content of phenolic compounds in plant samples ranged from 100.75 ± 3.87 mg/g (Yashkinsky district) to 190.95 ± 7.34 mg/g (Belovsky district). The content of chlorogenic acid in the studied samples was from 0.14 ± 0.01 mg/g to 1.16 ± 0.04 mg/g. Isorhamnetin glucoside was found only in samples of plants from two districts - Prokopievsky (41.39 ± 1.58 mg/g) and Belovsky (95.0 ± 3.66 mg/g). The content of glucosides of kaempferol ranged from 0.38 ± 0.01 mg/g to 0.55 ± 0.02 mg/g. Its content is almost twice as high as the content in the well-known analogues of Astragalus. Apigenin-7-glucoside was isolated in Astragalus samples for the first time, in a small amount (3.34 ± 0.13 mg/g) in a sample of plants of one growing zone. Studies have confirmed that the content of flavonoids in plants significantly depends not only on the genetic characteristics of plants, but also on the hydrothermal regime, the climatic conditions of different botanical and geographical areas of the habitat. This work shows that Astragalus danicus L. growing in Kemerovo region is a promising raw material for pharmacological preparations.