Abstract:The effects of tonifying the kidney and strengthening the“Yang”preduced by the extracts of Chinese herbs Epimedium wushanense and E. pubescens were studied in this paper. The results showed that both two herbs could de-crease the concentration of plasma middle molecular substances and increase the concentration of plasma sulfhydrylgroup of“Yang-deficiency”model mice,thus suggesting that the above-said tonifying and strengthening effects of Her-ba Epimedii may result from its effects on middle molecular substances and sulfhydryl group,so as to strengthen thebedy resistance and eliminate the invading pathogenic factors.