Background and Objectives: Pro-inflammatory cytokines interleukin 17A (IL-17), leptin, and adiponectin have been associated with obesity and insulin resistance. Moreover, differences in sex and ethnicity as well as plasma concentration of adipocytokines and cytokines have been associated with the risk of insulin resistance. This study was conducted to elucidate whether sex differences exist in the risk of insulin resistance in Indonesian adoles- cents and to determine how plasma leptin, adiponectin, and IL-17 predict insulin resistance. Methods and Study Design: The study participants were 69 obese–overweight boys, 53 obese–overweight girls, 59 non-obese boys, and 50 non-obese girls aged 15–18 years. Insulin resistance was determined using the homeostatic model assess- ment of insulin resistance index. Plasma IL-17, leptin, and adiponectin were measured using ELISA. Data were analysed using one-way ANOVA and linear regression analysis. Odd ratios [ORs; 95% confidence intervals (CIs)] were analysed to estimate the risk of insulin resistance; the significance level was set at 95%. Result: The OR (95% CI) for insulin resistance was higher in obese–overweight boys than in obese–overweight girls. The plasma IL-17 was higher in boys, whereas plasma adiponectin and leptin were significantly higher in girls. In all partici- pants, obesity status and plasma leptin were the most efficient predictors of insulin resistance, whereas the IL-17 could not significantly predict insulin resistance. Conclusion: Sexual dimorphism exists in IL17 as well as leptin and adiponectin in adolescents. Plasma IL-17 cannot be used to predict insulin resistance in adolescents of both sex.