Bisphenol A (BPA) is one of the endocrine disrupting chemicals (EDCs) to which humans are continuously exposed. Studies have revealed that BPA is pharmacologically estrogenic by binding to estrogen receptors even at a very low concentration. This study compared the effects of low (100 μg) dose with high (10 mg) dose of BPA on body weight, insulin resistance and plasma glucose in 30 male Wistar albino rats. The rats were divided into 5 groups of 6 animals each, and were injected with corn oil (Group 1), 100μg/kg BPA(Group2), 10mg/kg BPA(Group 3), 12mg/kg Flutamide (Group 4) and 1mg/kg Testosterone propionate (Group 5) for 4 weeks. Blood samples were drawn at baseline, after 2 and 4 weeks for the determination serum parameters. In addition insulin tolerance test (ITT) was carried out after 2 weeks of treatment. The ITT result revealed that the BPA-treated groups showed lower blood glucose concentration after 30 minutes of insulin injection compared with the control groups. At the end of 4 weeks, the administration of 10mg of BPA significantly p <0.05 increased the % weight gain by 100% and significantly (p<0.05) lowered plasma glucose concentration compared with other groups. The results revealed that exposure to high level of BPA may result in obesity while chronic exposure to both high and low level of BPA may lead to increased production of insulin which may subsequently lead to insulin resistance.