Abrus precatorius seeds are said to possess fertility regulating activity. Hence, the50% alcoholic extract of seeds at doses of 50, 100 and 200 mg/kg b.w. administered orally for 60 days to 03 groups (does wise) each includes 05 male Guniea pigs. First group served as control (vehicle treated). After 60 days of feeding of doses the body and genital organ weight were noted histopathological changes were observed in genital organs such as testes, epididymes and vasa deferentia and compared with control animals. The body and genital organ weight were not much affected. A significant weight reduction of genital organ was noted. At higher doses, an arrest of spermatogenesis was observed at various stages in sominiferous tubules. No mature spermatozoa could be seen in somniferous tubular lumen. The epididymes and vasa deferentia were also devoid of spermatozoa. It is concluded that at higher doses, the treated male G. pigs became a zoospermic. It is clearly indicated that the seeds of this plant has potentiality to arrest spermatogenesis in male and thus regulate the fertility of male animals.