Although the genus Limonium was widely used in traditional medicine, few studies have focused on the biological capacities of different species of this group. In this study, biological activities of hexanic, dichloromethane, ethanolic, and methanolic extracts, related to their phenolic contents, and HPLC phytochemical analysis of the halophyte Limonium densiflorum were investigated on human cell lines and murine macrophages. The evaluation of the antioxidant capacities using oxygen radical absorbance capacity (ORAC method), superoxide anion scavenging activity and a cell based-assay (WS-1), showed that shoot methanol extract exhibited the highest antioxidant activity. Moreover, this extract demonstrated the best anti-inflammatory activity, inhibiting NO release by 80% at 160 mu g/ml in LPS-stimulated RAW 264.7. The dichloromethane extract displayed the highest anticancer activity against human lung carcinoma (A-549) and colon adenocarcinoma cell lines (DLD-1) with IC50 values of 29 and 85 mu g/mL, respectively. The estimation of phenolic content showed that methanolic and ethanolic extracts had the highest amounts (56.1 and 48.1 mg EGA/g DW, respectively). The identification of phenolic compounds in methanolic extract of the plant using RP-HPLC, revealed that trans 3-hydroxycinnamic acid, myricetin and isorhamnetin were the major molecules present which may be responsible for the biological activities of the species. Results obtained indicated that L. densiflorum extracts can be used potentially as a readily accessible and valuable bioactive source of natural products. (C) 2015 SAAB. Published by Elsevier B.V. All rights reserved.