Background: Adolescents have unique sleep patterns and reduced sleep duration due to hormonal, activity, and environmental influences. Short sleep duration could be a factor in obesity, and insulin resistance might cause various metabolic problems. Several previous studies have conveyed different results. The present study analyzed the relationship between sleep duration and insulin resistance in obese adolescents with metabolic syndrome. Methods: A total of 62 adolescents aged 13-15 years and 62 adolescents aged 16-18 years who met the criteria for metabolic syndrome based on the International Diabetes Federation 2007 from 12 secondary schools in Surabaya and Sidoarjo. Insulin resistance was determined using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) with a cutoff value of >3.54. Sleep duration was determined based on direct interviews with research subjects and classified as short sleep duration when sleep duration was < 8 hours. The obtained data were analyzed using Chi-Square, Mann-Whitney, and T-test (significant at p<0.05). Results: The subjects were dominated by male adolescents (67.7%). There was a meaningful relationship between age and sleep duration (p = 0.035). The 16-18 year age group had more short sleep duration. The results of the analysis showed that there was a relationship between short sleep duration and the incidence of insulin resistance in both age groups, in the 13-15 year age group (PR 1.78; phi coefficient 0.430; p<0.001) and in the 16-18 year age group (PR 2.90; phi coefficient 0.478; p<0.001). Conclusion: Short sleep duration is associated with insulin resistance in obese adolescents with metabolic syndrome.