Background: Obesity continues to increase in the United States (US) and elsewhere, with a number of published dermatologic associations. The purpose of this study was to characterize obesity among US office visits for dermatologic diseases. Methods: Data from the 2005 to 2011 National Ambulatory Medical Care Survey (NAMCS) and National Hospital Ambulatory Medical Care Survey (NHAMCS) were searched for the most common dermatologic diagnoses for which body mass index (BMI) could be classified. Results: For all dermatologic patient visits, 10% were underweight, 36.5% were normal weight, 23.8% were overweight and 29.7% were obese. Increasing age predicted the yearly increased likelihood of obesity (OR 1.02; 95% CI 1.01, 1.02; p<0.0001). Logistic regression controlling for age, sex, race and dataset found that in addition to age, NHAMCS dermatologic diagnosis patients were more likely to be obese than NAMCS patients (OR 1.22; 95% CI 1.03, 1.45; p=0.02). Specific diseases were found to have the highest obesity rates, including psoriasis, hidradenitis suppurativa and acanthosis nigricans. Conclusion: A large proportion of dermatologic diagnosis patients are obese, and awareness could lead to interventions that may improve their disease and decrease risks of comorbidities.