Icariin (ICA) is one of the main active ingredient,isolated from Herba epimedii of Chinese medicine plant.It is generally used to treat osteoporosis,kidney dificiency and others.In this paper,the pharmacological effects of Icariin were summarized in the fields of anti-osteoporosis,antitumor,immunomodulation,improving reproduction,lowering blood sugar and protecting nervous system in the literatures.This paper provides a basic understanding of icariin for future studies.