Objective: The rate of heart disease is 1.5-fold greater among Aboriginals compared to the general Canadian population. Risk factors such as smoking, hypertension, dyslipidemia, obesity and diabetes are also more prevalent. For example, type 2 diabetes is 3.6 - 5.3 times more prevalent among Aboriginals. Obesity is relatively common in diabetes, contributing to poor diabetes control and the development of its associated complications. It is of interest to compare the prevalence of obesity among Aboriginals with diabetes to all Canadians with diabetes. Methods: A MEDLINE search was conducted (1966-2007) using the following MeSH terms: Indians – North American, Canada, diabetes mellitus, obesity and body mass index (BMI). Population-based studies reporting the proportion of Aboriginals with diabetes that were overweight (e.g. = 25 kg/m2 for women, = 27 kg/m2 for men) or obese (= 30 kg/m2) were retrieved. Prevalence estimates of elevated BMIs for Canadians with diabetes were obtained from the LCDC National Population Survey (1996-1997) and the Ontario Diabetes Database (1996-1997; Ontario Health Survey). Results: Twenty-three studies were retrieved. Seventeen studies were excluded because either the patient populations or definitions of obesity/overweight differed between studies. Ranges of 76.2 - 86.5% of Aboriginals with diabetes were either overweight or obese compared to 59.4% of all Canadians with diabetes. Furthermore, 44.1 - 69.6% of Aboriginals with diabetes were obese compared to 28.6% of all Ontarians with diabetes. Conclusion: When compared with the general Canadian population with diabetes, elevated BMI is more commonly observed among Aboriginals with diabetes. These findings suggest that obesity, as a risk factor for poor diabetes control and heart disease, is not optimally managed within the Aboriginal diabetes population and may pose a great burden to the Aboriginal community. The precise impact of obesity and diabetes on the health of Aboriginals warrants further research.