Type 2 diabetes mellitus is a chronic, progressive illness that causes considerable morbidity and premature mortality. Vanadium is a trace mineral that has been claimed to be effective in controlling blood glucose levels in diabetic patients. A randomised placebo-controlled study was conducted to evaluate the effect of sodium metavanadate on selected biochemical markers in type 2 diabetic patients. Forty patients were enrolled and half of them received 100 mg sodium metavanadate daily for 6 weeks while the other half were placebo subjects. The mean age of the patients was 53.1 ± 8.5 years. Body mass index (BMI), blood pressure(BP), fasting blood sugar (FBS), 2-h postprandial glucose, glycated hemoglobin (HbA1C), triglyceride(TG), total cholesterol (TC), low-density lipoproteins (LDL), high-density lipoproteins (HDL) were determined before the start and at the end of the study. Levels of FBS, HbA1C, TC and LDL in the diabetic subjects decreased after six weeks on sodium metavanadate, but the differences were not statistically significant on comparing between pre- and posttrial levels. Based on the results, this study did not find sodium metavanadate of beneficial use as a form of vanadium supplementation among patients with type 2 diabetes.