BACKGROUND Although various modalities of hemodialysis (HD) are presumed to have different effects on insulin resistance (IR), the relationship between hemodiafiltration (HDF) and IR has not been fully evaluated. METHODS In a cross-sectional study, 82 non-diabetic HD patients were enrolled. The patients were divided into two groups according to the median homeostasis model assessment index (HOMA-IR) value of 1.685. Clinical and biochemical data were compared, and multivariate logistic regression analysis was performed to identify the independent factors associated with higher HOMA-IR. RESULTS The higher HOMA-IR group had increased body mass index (BMI), decreased HDL cholesterol, and lower beta-2 microglobulin reduction rate (β2-MG RR) compared to the lower HOMA-IR group. HOMA-IR was significantly correlated with β2-MG RR. In addition, HDF patients had lower HOMA-IR levels compared with low flux hemodialysis patients. On multivariate logistic regression analysis, BMI and HDF treatment were independent factors associated with higher and lower HOMA-IR, respectively. CONCLUSION This study suggests that HDF treatment may reduce IR in non-diabetic HD patients.