Abstract: OBJECTIVE To explore the clinical application value of serum procalcitonin (PCT)in the treatment of stroke associated pneumonia(SAP),so as to provide evidence for the diagnosis and treatment of SAP. METHODS A total of 100 SAP patients hospitalized in our hospital from Jul.2013 to Mar.2015 were collected, and randomly divided into conventional treatment group (control group) and the guidance of PCT in treatment group (test group), with 50 cases in each group. The clinical pulmonary infection score (CPIS), tracheal secretions, chest X-ray data, body temperature, blood routine, and trachea suck out bacterial culture of the patients were detected. The antibiotics limit daily dose (DDD), antibiotic use time, CPIS, inflammatory indicators (WBC, CRP, PCT), pneumonia related mortality, pneumonia related pneumonia hospitalization days, and medical cost of the two groups were compared. RESULTS The general indicators(CPIS, WBC,CRP, and PCT) of the two groups of patients had no significance. The CPIS score and inflammatory indexes had no significance of the two groups 1 day after treatment. Five days after treatment, the CPIS score and inflammatory indexes of test group were significantly lower than those of control group. Full use of antimicrobial treatment limit daily dose (DDD), antibiotic use time, pneumonia related hospitalization days, and pneumonia related medical cost of test group were significantly lower than those of control group. The pneumonia related mortality of control group was higher than that of test goup, the pneumonia related mortality of control group was higher than that of test group, but the difference was not significant. CONCLUSION PCT level can be monitored as a good clinical indicator for the diagnosis, treatment and clinical medication of SAP patients, and can play a role in the diagnosis and treatment of SAP.