In the current presentation, our latest results performed on Lycopodium clavatum L the most common species in Turkey, are given in terms of biological activity, which include antibacterial, antifungal, antiviral, cytotoxic, antioxidant, anti-inflammatory and immunomodulatory activities of this fern. Antioxidant activity of the plant was assessed on the basis of the radical scavenging effect of the stable 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) using ELISA microplate reader. However, all of the extracts had insignificant antiradical effect towards DPPH. For determination of antibacterial activity, standard and the isolated strains of a number of bacteria along with standard strains of Candida albicans, and C parapsilosis for determination of antifungal activity were employed. All of the extracts possessed noteworthy activity against ATCC strain of Streptomyces aureus (4 mu g/ml), while the LC extracts showed reasonable antifungal effect. In order to establish the antiviral activity, Herpes simplex virus (HSV) and Parainfluenza-3 virus(PI-3) were used and maximum cytopathogenic effect (CPE) concentrations as the indicator of antiviral activity of the LC extracts were determined. However, we found out that only the chloroform extract was active against HSV (16-8 mu g/ml), while the petroleum ether and the alkaloid extracts inhibited potently PI-3 (16-4 mu g/ml and 32-4 mu g/ml, respectively). Moreover, anti-inflammatory potential of the plant was determined using acetic acid-induced increase in capillary permeability assessment in mice and the chloroform extract and the alkaloid fraction displayed marked anti-inflammatory effect at dose of 500 mg/kg. Gas chromatographic-mass spectrophotometric (GC-MS) analysis of the active fraction pointed out to lycopodine (84.5%) as the major component.