Lichens have been commonly used in traditional medicine. Biological potential (anti-proliferative, antioxidant and anti-bacterial) and chemical content of five lichen species (E. divaricata, L. vulpina, L. pulmonaria, R. fraxinea and U. florida) were assessed in relation to traditional knowledge. Consistent with folkloric usage, the strongest anti-proliferative activity was observed with L. pulmonaria against human hepatocellular carcinoma (HepG2/C3A) cell line. L. pulmonaria also showed the highest antioxidant capacity. While E. divaricata had the most phenolic content, the highest flavonoid content was determined in L. pulmonaria. All lichen extracts showed the best antibacterial activity against Gram-positive bacteria and only R. fraxinea had a broad spectrum of antibacterial activity. HPLC-DAD analysis revealed that L. pulmonaria and U. florida were the best sources of stictic acid and usnic acid, respectively. Traditional usages of tested lichens were justified with this study and nutraceutical potentials of them were revealed.