BACKGROUND/OBJECTIVES: Lipid accumulation product (LAP) is an index, which combines waist circumference (WC) and triglyceride (TG) reflecting lipid accumulation. The aims of the study were to explore the relationship between LAP and insulin resistance (IR) and to assess whether LAP was superior to WC and body mass index (BMI) in identifying IR. SUBJECTS/METHODS: The study was cross-sectional and included 2524 non-diabetic subjects from China. The blood pressure (BP), anthropometric measurements, glucose levels, insulin levels and a fasting lipid profile were measured. BMI, the homeostasis model assessment of IR (HOMA-IR) and LAP were calculated. RESULTS: In both sexes, BP, BMI, total cholesterol (TC), non high-density lipoprotein cholesterol (non-HDL-C), HOMA-IR, fasting and postprandial glucose levels increased across LAP quartiles (Po0.001), while HDL cholesterol (HDL-C) levels decreased across LAP quartiles (Po0.001). Pearson's correlation analysis demonstrated that HOMA-IR was correlated with LAP, BMI, WC, TG, HDL-C and non-HDL-C in both sexes (Po0.001). Multivariate analysis demonstrated that LAP had a greater impact on HOMA-IR than BMI and WC. CONCLUSIONS: LAP is closely associated with HOMA-IR and is a powerful index that outperforms BMI and WC in identifying IR in non-diabetic individuals.