The association between obesity and the risk of gliomas remains unclear. We sought to evaluate the potential association between general and abdominal obesity and the risk of gliomas based on a nationwide population-based cohort study of Koreans. Using data from the Korean National Health Insurance System cohort, 6,833,744 people older than 20 years who underwent regular national health examination in both 2009 and 2011 were followed until the end of 2017. We documented 4,771 glioma cases based on an ICD-10 code of C71 during the median follow-up period of 7.30 years. Individuals with a body mass index (BMI) ≥ 25.0 kg/m2 were at significantly higher risk of gliomas than those with a BMI < 25.0 kg/m2 (HR 1.08 CI 1.02-1.15). Individuals with a waist circumference (WC) ≥ 90 cm (males)/85 cm (females) also had a significantly higher risk of gliomas than those with a WC < 90 cm (males)/85 cm (females) (HR 1.16 CI 1.09-1.24). In the group with a BMI ≥ 25.0 kg/m2, individuals with abdominal obesity were at significantly higher risk of gliomas (HR 1.18 CI 1.09-1.27) than those without abdominal obesity. The role of abdominal obesity in this association was stronger in women than in men. To our knowledge, this is the first demonstration that obese people may be at higher risk of gliomas, especially centrally obese people from an Asian population with a BMI ≥ 25.0 kg/m2. Loss of visceral fat in people with abdominal obesity may reduce their risk of gliomas.