As elevated triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) ratio has been described as predictor for cardio metabolic disease with insulin resistance (IR) in the background, the aim was to assess the relationship between this ratio and IR in youth. Oral glucose tolerance test was performed in 318 Brazilian students (175 girls, 11.2 ± 3.2 years, BMI_z-score 1.2 ± 1.4 SD). Measurements: BMI, waist circumference (WC), blood pressure (BP), lipids, insulin and high sensitivity C-reactive protein (hsCRP). Excessive weight and abdominal obesity were defined using BMI_z-score and WC and IR by Homeostasis model assessment-insulin resistance (HOMA-IR). TG/HDL-C median was 2.37. There was an association between TG/ HDL-C and WC, systolic and diastolic BP, insulin, HOMA-IR, hsCRP, (p < 0.001). Stratified TG/HDL-C into two groups, based on a cut off point of 2.73 (Group 1: <2.73 and Group 2: ≥2.73). Adjusting for age, gender, ethnicity TG/HDL-C was an independent variable predicting IR (PR = 1.44; CI: 1.07 -1.96; p = 0.018). For every 1 (cm) in WC increased there was an addition of 0.04 of the value of TG/HDL-C and in those with TG/HDL-C ≥ 2.73 for every 10 (cm) increase in WC there was an improve of 4% in the ratio. In conclusion: In youth, the TG/HDL-C ratio could be a useful index for identifying groups with IR.