For community acquired pneumonia (CAP), the discrimination between typical and atypical bacterial causes could influence antibiotic choice and outcome of patients. Objective of this study was to evaluate the utility of serum procalcitonin (PCT) level as a diagnostic and prognostic marker for CAP. Typical bacteria were isolated and identified by conventional methods. An indirect immunoflourescence assay was used to diagnose atypical bacteria. Serum level of PCT was measured by ELISA and clinical outcome was evaluated. Out of 240 enrolled CAP patients, 95 (39.6%) had bacterial etiology (30.8 % typical bacterial pneumonia and 8.8% atypical pneumonia). Ninety five bacterial CAP patients were divided into 3 groups; group 1 (mortality, 20.1%), group 2 (complications, 52.6 %) and group 3 (discharge, 26.3 %). Group 1 patients had the highest PCT level in serum compared to other groups with a statistically significant difference (P˂ 0.001). A statistically significant higher serum level of PCT was detected in typical than atypical pneumonia (P˂ 0.001). In conclusion, serum PCT level may serve as a diagnostic and prognostic marker in CAP.