Medicinal plants are widely used for the relief of disease symptoms or as dietary supplements. In recent decades, purple coneflower has become extremely well known. An infusion or tincture of purple coneflower can be prepared by anyone simply, inexpensively, and ecologically safely. Three plant parts of purple coneflower were used in the study: extracts from roots, flowers, and leaves were obtained using three different solvents (100% and 40% ethanol and water). High-performance liquid chromatography-mass spectrophotometer identified and quantified 23 individual phenolics. Pure (100%) ethanol gave the lowest yield of all the investigated phenolic compounds in all herb parts. Chicoric and caftaric acids were the major phenolic compounds in coneflower. Caftaric acid, with health promoting properties, was extracted best in a water solution from purple coneflower leaves (2673.31 mg/100 g dry weight [DW]) and chicoric acid, also with a beneficial effect on human health, yielded the highest levels in 40% ethanol solution from flowers (1571.79 mg/100 g DW) and roots (1396.27 mg/100 g DW).