OBJECTIVES/HYPOTHESIS: To analyze the association between sleep duration, metabolic variables, and insulin resistance in obese children with and without obstructive sleep apnea. The decline in sleep duration has paralleled a dramatic increase in the prevalence of obesity and diabetes, suggesting a mechanistic relationship. STUDY DESIGN: Retrospective, case series. METHODS: Consecutive obese patients 3 to 12 years of age who underwent polysomnography (PSG) and a metabolic panel and who completed a 14-item sleep questionnaire were analyzed. All laboratory testing was conducted within 3 months of PSG. Total sleep times were obtained from the PSG and confirmed by the questionnaire. RESULTS: A total of 171 patients (55.0% male) were studied. All patients were obese (body mass index [BMI] z score > 95th percentile). Patients were categorized into three groups: short sleepers, borderline sleepers, and optimal sleepers. Eighty-six (50.3%) patients were short sleepers, 71 (41.5%) were borderline sleepers, and 14 (8.2%) were optimal sleepers. The mean BMI z score was 3.13 +/- 1.3 in short sleepers, 3.3 +/- 1.1 in borderline sleepers, and 3.5 +/- 1.5 in optimal sleepers (P = .39). There was no statistical difference in high- and low-density lipoprotein levels (P = .21 and P = .76, respectively) and total cholesterol (P = .43) among subgroups. Triglycerides, blood glucose, insulin, and homeostasis model assessment-insulin resistance were significantly higher in short sleepers when compared to borderline or normal sleepers (P = .008, P < .001, P < .001, and P < .001, respectively). CONCLUSIONS: Short sleep duration was correlated with alterations in metabolic variables and insulin resistance in obese patients. This raises concern for development of comorbid conditions that can persist into adulthood. LEVEL OF EVIDENCE: 4 Laryngoscope, 127:2176-2181, 2017.