Clerodendrum Serratum is claimed to have use in reproductive related health problems. Objective: To study the potential anti-fertility effect of the methanolic extracts of Clerodendrum Serratum in mature male albino rats. Methods: The methanolic extract were given by oral gavages to rats in the in vivo test at a dose of 100, 300 and 500mg/kg of body weight for 30 days and antifertility effects assessed by various parameters in male rats. Statistical differences were determined by the ANOVA followed by Dunnet's test and the level of significance set at p