The aim of this study was to estimate the prevalence of Type 2 diabetes, impaired glucose tolerance (IGT), and obesity in the Mapuche natives from rural areas in Chile. This cross-sectional study involved men (n = 95) and women (n = 224) older than 20 y from an aboriginal ethnic group (Mapuches), residing in rural communities from the south of Chile. Prevalence of Type 2 diabetes and IGT was calculated according to the World Health Organization criteria. Data on age, degree of ancestral purity, obesity, and hypertension were also obtained. The prevalence of Type 2 diabetes in rural Mapuche natives was estimated as 3.2% (95% CI: 0.7–9.0) in men and 4.5% (95% CI: 2.2–8.1) in women. The overall prevalence of obesity was 56.1% (95% CI: 50.5–61.6): 40.0% (95% CI: 30.1–40.8) in men and 62.9% (95% CI: 56.3–69.3) in women (P value < 0.001). These data suggest that the prevalence of obesity and Type 2 diabetes has been increasing during recent years in the Mapuche communities. The prevalence estimated in this study is higher than that reported 15 y ago. This suggests an important role of lifestyle changes as a possible explanation for epidemiologic transition.