Abstract: AIM To investigate the effects of contrast temperature on the prevalence of contrast-induced nephropathy (CIN). METHODS A total of 157 patients who underwent percutaneous coronary intervention were randomly divided into 20℃ iodixanol group (n=77) and 37℃ iodixanol group (n=80). Hemorheology indexes were determined prior and post-index procedure, respectively. Meanwhile, serum cystatin C and creatinine were also detected within 24 h prior to index procedure and at 12, 24, and 48 h post-index procedure, respectively. The effects of two types of contrast temperature on renal function and hemorheology indexes were analyzed. RESULTS Serum cystatin C at 24 h post-procedure and creatinine at 48 h post-procedure were higher than pre-procedure in 20℃ iodixanol group, which were both statistically significant (P<0.05). Compared to pre-procedure, both high and low shear rate blood viscosity post-procedure were statistically significantly increased in 20℃ iodixanol group. Serum cystatin C at 24 h post-procedure and creatinine at 48 h post-procedure in 37℃ group were significantly lower than in the 20℃ group, respectively (P<0.05). Compared to the 20℃ group post-procedure, both high and low shear rate blood viscosity post-procedure were statistically significantly lower in 37℃ iodixanol group (P<0.05). The prevalence of CIN in 37℃ iodixanol group was statistically significantly lower than in the 20℃ iodixanol group (2% vs. 8%, P<0.05). CONCLUSION The prevalence of CIN in the 37℃ iodixanol group is significantly lower than in the 20℃ iodixanol group.