Abstract: Background and Objective: Previous studies demonstrated the toxicity of cypermethrin, a commonly used insecticide in vector control and agriculture in Cameroon. Medicinal plants such as Bersama engleriana (B. engleriana) are considered as potential source remedy in local medicine. This study aimed at evaluating the protective effects of B. engleriana extracts on cypermethrin toxicity on haematological and biochemical parameters in male guinea pigs. Materials and Methods: Eighty animals were divided into 8 groups, which received daily distilled water (2 mL kg–1), cypermethrin alone (137.5 mg kg–1) or co-administered cypermethrin and B. engleriana aqueous/ethanol extract at the doses 50, 100 and 200 mg kg–1. The products were administered orally for 13 weeks and the animal body weight recorded weekly. At the end of the treatment, blood was collected for determination of haematological and biochemical parameters and differences between groups were determined using one way ANOVA followed by the Duncan’s test. Results: Cypermethrin increased (p<0.05) the total white blood cells and lymphocytes number and moderately decreased red blood cells. The cypermethrin-induced changes on blood cells count were prevented when the pesticide was co-administered to the animals with either aqueous or ethanol extract of B. engleriana. Moreover, impairment of liver and kidney parameters observed in the animals exposed to the pesticide was alleviated with B. engleriana treatment. Conclusion: This study concluded the beneficial effects of B. engleriana in alleviating alteration of haemato-biochemical parameters induced by cypermethrin. The B. engleriana extract can be considered as a valuable remedy in prevention of pesticide induced toxicity.