Chronic feeding of carcinogens p-dimethylamino azobenzene (initiator) and phenobarbital (promoter) for 90 and 120 days elevated activities of acid and alkaline phosphatases, levels of blood glucose and cortisol and decreased the activities of glutathione reductase, succinate dehydrogenase, and blood cholesterol and hemoglobin contents, and levels of serum estradiol and testosterone in mice. Levels of these biomarkers in both liver and spleen tissues were positively altered along with a significant reduction of tumor incidence in liver of carcinogen intoxicated mice treated with spore extract of Lycopodium clavatum. The results validate the use of this plant extract in complementary and alternative medicines against hepato-toxicity.