Objective To investigate the value of procalcitonin (PCT) at admission for severity stratificaton and prognosis prediction of community-acquired pneumonia (CAP), and assess the ability of the combination of PCT and the validated pneumonia risk scores (PSI and CURB-65) for predicting 30-day mortality. Methods A retrospective study was performed in 150 hospitalized CAP patients admitted in the Department of Respiratory Medicine of General Hospital of Tianjin Medical University between March 2015 and March 2016. The primary end point for this study was mortality within 30 days. Sensitivity (SEN), specificity (SPE), positive and negative predictive value (PPV, NPV) of PCT for assessing mortality was calculated and compared to validated pneumonia risk scores. Results In the 150 CAP patients enrolled, there were 77 males and 73 females with an average age of 58.4±16.3 years. Twelve (8%) patients died within 30 days. The non-survivors had significantly higher median PCT level (4.25 ng/mlvs. 0.24 ng/ml) and C-reactive protein (CRP) level (14.60 mg/dlvs. 5.10 mg/dl) compared with the survivors. The median PCT level was significantly higher in the patients with more severe disease assessed by two risk scoring systems. Combination of PCT with risk scores can improve prognostic value for predicting 30-day mortality of CAP. Conclusions The level of PCT at admission is more useful than the traditional biomarkers for the severity stratification and prognosis prediction of CAP. It can well determine patients at low risk of mortality from CAP. There is no advantage of PCT compared to PSI or CURB-65, so we recommend combination of PCT to risk sores to predict 30-day mortality of CAP.