Phenylpropanes, flavonol derivatives, biflavones, proanthocyanidins, xanthones, phloroglucinols, some amino acids, naphthodianthrones and essential oil constituents are the natural plant products known from the crude drug of Hypericum perforatum, Hyperici herba. These compounds are discussed with respect to structural features, their concentration, biological activities and their possible contribution to the clinically demonstrated antidepressant efficacy of extracts obtained from Hyperici herba.