Objective: The development of new effective drug to stimulate the spermatogenesis on the patients with various causes of male infertility has been proposed in the clinical field.We studied the usefulness of the two herbal extract mixture,KH-465,consisted of Epimedium Koreanum and Angelica Gigas as a spermatogenesis enhancer.Methods: Experimental spermatogenic failure was made by administrating leuprolide acetate(Leuprin(@),Takeda Pharm.)3.75 mg intramuscular injection in 12 weeks Sprague-Dawley rats.Rats were divided to 5 groups of control group and experimental group Ⅰ,Ⅱ,Ⅲ & Ⅳ with Leuprin only,Leuprin & depot testosterone 10.5 mg intramuscular injection,Leuprin & 4 weeks administration of KH-465 400 mg/kg,and Leuprin & 4 weeks administration of KH-465 600 mg/kg,respectively.The weight changes of testis and epididymis,serum hormone levels of FSH,LH,T and free T,sperm count and motility within epididymis and the level of oxidative stress with SOD and OHdG were estimated.Results: The weight changes of testis and epididymis were not significant among control and all experimental groups.T,free T and epididymal seminal parameters were significantly increased in groups Ⅲ & Ⅳ,but FSH and LH not changed.Oxidative stress markers were improved significantly only in group Ⅳ.Conclusions: The enhancing effect of KH-465 herbal extract on spermatogenesis was suggested from this result.Additionally,the separation of pure effective components from herbal extract in this study and the mechanism of its effect would be performed in the future.