The effect of Momordica charantia leaf extract was evaluated on male wistar rats. The animals were randomly assigned into three (3) groups of six (6) rats each. Group one (1) served as control and received distilled water. Group two (2) and group three (3) received 200mg/kg and 400mg/kg of the hydromethanol (20%:80%) extract respectively. In the final 10 days of study, the males were co-habited with female rats [1 male:2 females]. Results obtained showed that the extract significantly (P<0.05) reduced Fertility index and percentage fertility of male rats. Decreased sperm quality previously observed with the extract of M. charantia with associated reductions in serum Testosterone level may be responsible for this observation.