Abstract: The present study investigated the effect of aqueous extracts of Leptadenia hastata on male reproductive function. For acute toxicity nine groups of 6 male mice received orally, respectively 50, 100, 200, 500, 1000, 1500, 2000, 3000 and 4000 mg kg-1 of L. hastata aqueous extracts. The results showed the non toxic effect of L. hastata aqueous extracts. Rat weight gain and adrenals weight did not have significantly change. Seminal vesicles, prostate, levator ani plus bulbocavernosus muscles (LABC), cowpers glands, coagulant’s glands weights were significantly decreased with 200, 400, 800 mg kg-1 compared with controls. The serum testosterone level, the fructose and protein content of seminal vesicles and prostate were also significantly decreased with 200, 400, 800 mg kg-1 compared with the controls. Total protein, total cholesterol, HDL cholesterol, blood sugar and hematocrit on blood and serum did not have significantly change. Overall, these results indicate the anti-androgenic effect of L. hastata aqueous extract by Hershberger assay.