Background : The prevalence of obesity and related comorbidities is increasing worldwide, including in Korea. The Korean Society for the Study of Obesity released the Obesity Fact Sheet 2017 to address this problem in the Korean population. Methods : Data from the National Health Insurance Service Health Checkup database from 2006 to 2015 were standardized by age and sex using the 2010 Census. The definition of obesity was a body mass index (BMI) ≥25 kg/m², and that of abdominal obesity was a waist circumference ≥90 cm in men and ≥85 cm in women. Multivariate adjusted Cox regression analysis was conducted, and hazard ratios (HRs) with 95% confidence intervals were calculated for comorbidities. Results : From 2009 to 2015, the prevalence of obesity increased from 29.7% to 32.4%, and that of abdominal obesity increased from 18.4% to 20.8%. Obesity with abdominal obesity also increased from 15.1% to 17.7%. Between 2014 and 2015, the prevalence of obesity increased until 30–40 years of age, but decreased from 40–50 years of age in men. In women, it increased until the mid-70s, and decreased thereafter. Abdominal obesity increased from 20–30 years of age to 70–80 years of age, but decreased thereafter. The HRs for type 2 diabetes mellitus, hypertension, dyslipidemia, myocardial infarction, and ischemic stroke were elevated in subjects with abdominal obesity, and their incidence increased as the BMI increased, but slowed down at BMI ≥35 kg/m². Conclusion : Based on the Obesity Fact Sheet 2017, strategies for reducing the prevalence of obesity and abdominal obesity are essential.