The present study aimed to evaluate the protective effects of aqueous extract of Bersama engleriana leaves against cypermethrin-induced oxidative stress and reproductive toxicity. Thus, fifty male guinea pigs were divided into 5 groups (G1, G2, G3, G4 and G5) of 10 animals each. During 90 days, animals of G1 were orally given 1 ml/kg of body weight (bw)/day of distilled water, while the other groups received 137.50 mg/kg bw of cypermethrin. In addition, G3, G4 and G5 received respectively 50, 100 and 200 mg/kg bw of aqueous extract of Bersama engleriana leaves. At the end of the treatment period, the testicular concentration of malondialdehyde and the activities of superoxide dismutase and catalase decreased significantly (P<0.05) in guinea pigs exposed to cypermethrin and aqueous extract of B. engleriana leaves compared to those exposed to cypermethrin only (G2), while the reverse was observed with the activity of peroxidases. The time of reaction of male guinea pig in the presence of females and the percentage of abnormal spermatozoa decreased significantly (P<0.05) in animals treated with the insecticide and the aqueous extract of B. engleriana leaves compared to G2 animals. The weight of testes, serum level of testosterone, sperm count, mobility and percentage of spermatozoa with entire plasma membrane increased significantly (P<0.05) in guinea pigs given extract compared to those submitted to cypermethrin only. Thus, the aqueous extract of Bersama engleriana leaves protected male guinea pigs against cypermethrin toxicity.