This paper examines regional changes in the prevalence of overweight (BMI ³ 25 kg/m²) and obesity (BMI ³ 30 kg/m²) among Austrian adults (aged ³ 20 years) during a 35-year period, taking into account the social inequality with regard to obesity. Self-reported data from five cross-sectional nationally representative surveys (n = 178,818) conducted between 1973 and 2007 were analysed. The prevalence of overweight was higher in men than women (2007: 46.3 vs. 31.2 %;p < 0.001) and similar in all Austrian regions. There was a clear east-west gradient for obesity among both sexes, with the highest rates in Eastern Austria (in 2007, women: 18.1 %, men: 16.1 %;p < 0.001) and the lowest in Western Austria (in 2007, women: 12.6 %, men: 11.7 %;p < 0.001). Logistic regression analyses have shown a general decrease of overweight per year among women (OR = 0.991, 95 % CI 0.990–0.993) and men (OR = 0.999, 95 % CI 0.998–1.000), while the obesity prevalence has risen during the study period in every region (women: OR = 1.003, 95 % CI 1.001–1.005; men: OR = 1.011, 95 % CI 1.009–1.013), with the highest increase among women in Central Austria and men in Western Austria. Social inequalities for obesity showed a tendency to increase in the Western and Eastern region. Our results showed a significant regional difference for obesity prevalence during the entire study period. Obesity is a frequent health problem among Austrian adults residing in the Eastern region.