Objective To assess risk of hepatitis C virus (HCV) transmission in hemodialysis clinics in Lanzhou City by weighted rank-sum ratio (WRSR). Methods Five indexes were selected according to WRSR, index weight was determined by variation coefficient, and divided into three grades:high, medium and low according to risk level, risk of HCV transmission in 17 hospital hemodialysis clinics in Lanzhou was assessed. Results There was a high correlation between WRSR and probability units (r=0.981, linear regression equation:WȒSR=0.164×Y-0.311). The results of classification showed that risk of HCV infection was low in outpatient hemodialysis clinics of Y16 and Y17 hospitals, high in outpatient hemodialysis clinic of Y1 hospital, and medium in 14 other hospitals. Conclusion The risk levels of HCV transmission in hospital hemodialysis clinics in Lanzhou City vary greatly, and most of them are at medium and low risk levels. Prevention and control of HCV transmission should be strengthened in hemodialysis clinics according to their own weak links.