Resumen: Background: Obesity and sedentary behavior are risk factors acting independently in the development of type 2 diabetes. Aim: To investigate whether the association between diabetes and obesity is modified by the levels of sitting time (ST) in the Chilean population. Material and Methods: We included 4,611 participants from the cross-sectional 2009-2010 Chilean National Health Survey in this study. Diabetes was determined as fasting glucose levels ≥126 mg/dl. Body mass index (BMI) and waist circumference (WC) were measured using standardized protocols. Sitting time was assessed using the Global Physical Activity Questionnaire. The association among diabetes, obesity and ST was determined using logistic regression. Results: The odds for diabetes increased by 3.1-fold in people with high levels of ST and obesity in comparison to those with low levels of ST and normal BMI (Odds ratio (OR): 4.17 [95% confidence intervals (CI): 2.87 to 6.05], P < 0.01). The odds for diabetes increased by 2.7fold in highly sedentary subjects with central obesity (OR: 3.73 [95% IC: 2.61 to 5.33], P < 0.01) in comparison to those with low levels of ST and normal WC. Conclusions: Elevated levels of sitting time and obesity are associated with a higher odds of developing diabetes.