Abstract: OBJECTIVE To observe the dynamic changes of procalcitonin (PCT) and C-reactive protein (CRP) in acute stroke patients with nosocomial infection, and to explore the early diagnostic value of PCT and CRP in nosocomial infection after acute stroke. METHODS A total of 106 patients with acute stroke admitted to the hospital from Jan. 2016 to Jun. 2017 were enrolled, and divided into the infection group (44 cases) and the non-infection group (62 cases) according to the occurrence of nosocomial infection. The dynamic changes of PCT and CRP were observed in all patients on days 1, 2, 3, 5, and 7. The differences in PCT and CRP between the two groups were compared. ROC curve was used to analyze the value of PCT and CRP in the early diagnosis of nosocomial infection after stroke. RESULTS In 106 cases of acute stroke, 44 patients had nosocomial infection, the infection rate was 41.5%, dominated by lung infection, accounting for 61.36%. The PCT concentration of the two groups first increased and then decreased with the treatment time, and the peak of CRP occurred on day 3. The CRP concentration of the two groups first increased and then decreased with the treatment time, and peaked on the 5th day. On the 2nd, 3rd, 5th, and 7th day, the PCT concentrations of the acute stroke infection group were significantly higher than those of the non-infected group (P<0.001). On days 5 and 7, the CRP concentrations in the acute stroke infection group were significantly higher than those in the non-infected group (P<0.001). The sensitivity and specificity of the combined monitoring of PCT and CRP could be increased to 83.9% and 97.7%. CONCLUSION According to the dynamic changes of PCT and CRP as well as the related ROC curves, PCT and CRP have a certain role in the diagnosis of early nosocomial infection after stroke. PCT has more diagnostic value than CRP, and the combination of the two can improve the sensitivity and specificity of early diagnosis.