Abstract: OBJECTIVE To explore the levels and clinical significance of plasma levels of calcitonin (PCT) and C- reactive protein (CRP) in patients with dialysis complicated with infections. METHODS A total of 87 cases of hemodialysis and peritoneal dialysis patients from Sep. 2012 to Nov. 2014 were randomly selected as study objects, in which 39 cases of co-infected patients were selected as observation group, and 48 cases of non-infected patients were selected as control group. The levels of PCT and CRP of the two groups were compared, and the sensitivity and specificity of PCT and CRP and other indicators diagnosis were analyzed, in order to investigate their diagnostic values. RESULTS The PCT level and CRP level of observation group 7 days before dialysis had no significant difference compared with control group, while the PCT level and CRP level of the patients in observation group 4 days and 1 day before dialysis were significantly higher than that of control group (P<0.05). The positive rates of PCT and CRP of observation group the patients were 94.9%and 100% The procalcitonin test showed that there were 2 cases of patients with the PCT concentration <1.5ng/mL, 31 cases with 1.5~10ng/mL, and 6 cases with >10 ng/mL 6 cases in observation group; in the control group, there were 48 cases of patients with the PCT concentration <1.5 ng/mL, and 0 case with 1.5~10 ng/mL and >10ng/mL. Totally 37 strains of pathogenic bacteria were isolated from 39 cases of observation group, including 21 strains of gram-positive bacteria, 13 strains of gram-negative bacteria and 3 strains of fungi, accounting for 56.9%, 35.1%, and 8.1%, respectively. CONCLUSION PCT and CRP levels have important significance for the diagnosis of patients with infections, and can be used as an important reference for dialysis patients with infections.