The inverse association between obesity and education level has been demonstrated in many developed countries; however, few studies have investigated obesity in geriatric populations. This cross-sectional analysis explored the association between geriatric obesity and education level, along with other demographic characteristics in Taipei, Taiwan between 2013 and 2015. Taipei citizens ≥ 65 years (aborigines ≥ 55 years) were recruited to participate in the elderly health examination programme. Logistic regression was applied to analyse the relationship between obesity (defined as body mass index ≥ 27 kg/m2 in Taiwan) and education level among men and women after controlling for age, race, income status, and smoking status. A total of 28,092 men and 31,835 women were included in the final analysis. Compared to those with education years ≥ 16, older men and women with education years ≤ 12 had higher odds of being obese. The odds ratios increase as years of education decrease, and the trend is more pronounced among women. Aborigines had much higher chances of being obese among men and women, while there were no differences by income status. The results clarified the factors related to obesity in the elderly, and will be useful for authorities working to improve health outcomes among this population.