Abstract: This study was aimed at assessing the reproductive activities of male albino rats treated with crude leaf extract of Bougainvillea spectabilis. The total of thirty sexually matured male albino rats of about eleven weeks, weighing between 120-180 g were divided into five groups (A, B, C, D and E) with 6 rats in each group. Rats in group A served as the control and were fed with normal commercial feed only; groups B, C, D and E received 150, 300, 450 and 600 mg kg-1 Body Weight (BW) of the test substance, respectively. The results of the phytochemistry showed high content of phytates (49.27%) and other bioactive compounds in the leaf extracts. Results on the sperm parameters revealed significant reduction (p<0.05) in the sperm count, viability and motility. Sperm head abnormalities were also significant in the different groups with the highest recorded at 600 mg kg-1 BW (8.75%). Although, there were no significant difference in the epididymides weight of rats in the different groups, the testes weight was significantly reduced (p<0.05). From the present results, there is a dire need to always apply caution on the use of B. spectabilis in combating diseases considering the possible adverse effects that it could pose on spermatogenic pathways.