Childhood obesity is a nationwide epidemic with an estimated 16% to 18% of children and adolescents qualifying as obese and another 21% to 24% considered overweight. Obesity has been linked to an increased risk of developing serious infections. Healthcare Cost and Utilization Project-Kids' Inpatient Database 2009 was queried to analyze national trends in patient encounters, specifically those listing patients as comorbid obese and then identified those with urinary tract infection (UTI) as primary or secondary diagnosis. Propensity matching was used to calculate risk for UTI in the inpatient obese pediatric population. A total of 86 638 pediatric hospital admissions were enrolled in the study of which 41 819 included the diagnosis of obesity, and a UTI was diagnosed in 2445 of the cases. In a propensity-matched sample, matched for age, sex, race, and diabetes mellitus, the risk of UTI was increased by 45% in obese females. Obese males did not have a significantly increased risk for UTI.