Abstract: OBJECTIVE To investigate the significance of serum procalcitonin(PCT), C-reactive protein(CRP) and interleukin-6(IL-6) in the joint diagnosis of infection of urinary calculi, so as to provide references for clinical treatment of patients. METHODS A total of 46 cases urinary stones coinfected patients in our hospital from Feb. 2011 to Dec. 2014 were selected as observation group, and another 46 cases of normal people were selected as control group. The serum PCT, CRP, and IL-6 indexes of the two groups were compared, and its implications for the diagnosis of infection in patients with urinary stones were analyzed. RESULTS The CRP, PCT, and IL-6 of control group were (2.3±1.2)mg/L, (0.29±0.1)ng/L, and (3.4±4.2)ng/L, while in observation group were (17.5±2.4)mg/L, (5.7±1.8)ng/L, (76.4±25.6)ng/L, and the differences were significant (P<0.05). In observation group, the specific detection of CRP was 84.8%, the sensitivity was 76.1%, and the coincidence rate of diagnosis was 82.6%; specificity of PCT detection was 89.1%, the sensitivity was 82.6%, and the coincidence rate of diagnosis was 89.1%; the specificity of IL-6 detection was 86.9%, the sensitivity was 76.1%, and the diagnostic coincidence rate was 86.9%. The sensitivity and specificity of PCT detection were the highest, and the joint detection of the three indexes could improve the diagnosis rate. CONCLUSION Serum procalcitonin, C-eactive protein and interleukin-6 can be used as diagnostic indicators of urinary stones coinfected patients with high clinical significance.