Abstract: The pathogenesis of type 2 diabetes is a complex phenomenon. Many research works have implicated obesity and dyslipidaemia as possible causes of type 2 diabetes mellitus. The aim of this study was to determine the association between BMI, oxidative stress and skeletal muscle mass in the aetiology of type 2 diabetes. The study was conducted at the Komfo Anokye Teaching Hospital, Kumasi Ghana. The study involved 120 diabetic subjects and 80 non diabetics as control, matching age and sex with the diabetics. Anthropometric parameters measured include height, weight, waist circumference, hip circumference, thigh circumference, plasma glucose was determined by the enzymatic method and plasma creatinine concentration by the Jaffe reaction using creatinine reagent. Urine sugar was estimated using a urine test strip. Malonyldialdehyde level in serum was estimated spectrophotometrically according to the Buege and Aust method. The body mass index was significantly higher in the diabetics than the controls (26.45±6.49 and 22.13±3.30 kg m-2) (p<0.001), respectively. Fasting blood glucose levels were obviously higher in the diabetics than in the non-diabetics (9.925±0.544 and 5.448±0.88 mmol L-1) (p<0.0015). Serum MDA concentration was significantly higher in the diabetics than the controls (0.29±0.03-0.23±0.02 μmol L-1 (p<0.0502) while Serum creatinine of the diabetics was non significantly lower than that of the controls (98.70±53.94-101.9±34.00μmol L-1 (p<0.3677). Overweight, skeletal muscle and oxidative stress may play a significant role in the aetiology of type 2 diabetes or at least aggravate the diabetes.