According to the WHO data (2017), depression is the most predominant disease worldwide, with about 300 million people suffering from it, and bipolar disorder is the second most common. Therefore, it is relevant to research new medicines based on medicinal herbal raw materials with anti-anxiety and antidepressant effects. Common heather (Calluna vulgaris (L.) Hull.), a flowering plant of the Ericaceae family, is a promising species for research in this area. The aim of this study was to investigate the phytochemical profile and several biological activities of hydroethanolic dry extracts from the C. vulgaris herb. Nineteen phenolic substances were identified and quantified in the extracts by HPLC. The quantitative content of the basic groups of biologically active compounds was determined by spectrophotometry. Arbutin was dominant among the hydroquinone derivatives; chlorogenic acid among the hydroxycinnamic acids; rutin, hyperoside and quercetin-3-D-glucoside among the flavonoids; and (+)-gallocatechin and (-)-epigallocatechin among the tannin metabolites. The water and hydroethanolic extract were compared, the extract of C. vulgaris herb obtained with 70% hydroethanolic had the most pronounced anti-inflammatory, antimicrobial, anxiolytic, stress-protective, anti-anxiety and anti-depressant effects, and it is a promising substance for the development of new drugs or food supplements.