Epimedii Folium, a famous Chinese materia medica, is botanically originated from Epimedium L. species. Here Epimedium L. species were reviewed in phytochemistry, ethnopharmacology, ADME(absorption, distribution, metabolism, and excretion), and processing. They have been proven to possess the efficacy on anti-osteoporosis, antitumor, and treating sexual dysfunction in traditional Chinese medicines. More than 270 compounds have been isolated from the plants of Epimedium L., some of which could be metabolized into a series of metabolites after oral absorption by the active enzymes and intestinal microflora leading to various bioactivities. Polyglucosides(epimendins A-C) and the coresponding oligoglycosides(icariin and baohuoside I) play important roles in clinical application. Epimedii Folium, a famous Chinese materia medica, is botanically originated from Epimedium L. species. Here Epimedium L. species were reviewed in phytochemistry, ethnopharmacology, ADME (absorption, distribution, metabolism, and excretion), and processing. They have been proven to possess the efficacy on anti-osteoporosis, antitumor, and treating sexual dysfunction in traditional Chinese medicines. More than 270 compounds have been isolated from the plants of Epimedium L., some of which could could be metabolized into a series of metabolites after oral absorption by the active enzymes and intestinal microflora leading to various bioactivities. Polyglucosides (epimendins AC) and the coresponding oligoglycosides (icariin and baohuoside I) play important roles in clinical application.