Obesity is associated with chronic low-grade inflammation in which is the key in the pathogenesis Insulin Resistance (IR) and Metabolic Syndrome (MetS). Homeostasis model assessment of insulin resistance (HOMA-IR) has been validated as a surrogate measure of IR. The combination of HOMA and adiponectin, known as HOMA-AD was proposed to measure IR in adults. However, study on these indicators in obese adolescents is still limited. This study aims to analyse METS-IR and HOMA-AD to determine MetS and IR in obese adolescents. A cross-sectional study was conducted on obese adolescents who looked healthy from secondary schools in Surabaya and Sidoarjo, East Java, aged 12-18 years. Subjects were selected randomly and grouped into 2, namely MetS and non-MetS based on IDF 2000. Anthropometric examination and blood measurements, such as fasting blood glucose levels, lipid profiles, insulin, and adiponectin level were carried out according to standards. HOMA-IR, HOMA-AD, AND METS-IR were calculated using formula. Spearman’s Rho correlation were conducted between assessment tools (METS-IR and HOMA-AD) to identify the correlation with MetS component (lipid profile, FBG, and blood pressures). A receiving operation curve (ROC) performed to find area under curve (AUC) and cut-off points based on the biggest Youden index. A total of 250 subjects were enrolled the study, and found 103 subjects had MetS. METS-IR correlates with all lipid profile and blood pressures (p?<? 0.05). While HOMA-AD correlated with TG (r?=? 0.356, p?=? 0.000), systolic-BP (r?=? 0.188, p?=? 0.003), and HDL-c levels (r=-0.249, p?=? 0.000). Cut-off point for METS-IR to determines MetS in obese adolescents was??? 46.53 (sensitivity of 64.24% and specificity of 75.76%), while HOMA-AD was??? 0.43 (sensitivity of 71.52% and specificity of 59.60%). Cut-off point for METS-IR index to determines IR was??? 52.01 (sensitivity of 83.44% and specificity of 44.44%). Cut-off point for HOMA-AD to determine IR was??? 0.37 (sensitivity of 74.17% and specificity of 84.85%). METS-IR is better surrogate to determine MetS with cut-off point of??? 46.53, while HOMA-AD is better to determine IR with cut-off point??? 0.37 in obese adolescents. J. Med. Invest. 70: 7-16, February, 2023