Background/Aim. Early assessment of severity and continuous monitoring of patients are the key factors for adequate treatment of acute pancreatitis (AP). The aim of this study was to determine the value of procalcitonin (PCT) and Bedside Index for Severity in Acute Pancreatitis (BISAP) scoring system as prognostic markers in early stages of AP with comparison to other established indicators such as Creactive protein (CRP) and Acute Physiology and Chronic Health Evaluation (APACHE) II score. Methods. This prospective study included 51 patients (29 with severe AP). In the first 24 h of admission in all patients the APACHE II score and BISAP score, CRP and PCT serum concentrations were determined. The values of PCT serum concentrations and BISAP score were compared with values of CRP serum concentrations and APACHE II score, in relation to the severity and outcome of the disease. Results. Values of PCT, CRP, BISAP score and APACHE II score, measured at 24 h of admission, were significantly elevated in patients with severe form of the disease. In predicting severity of AP at 24 h of admission, sensitivity and specificity of the BISAP score were 74% and 59%, respectively, APACHE II score 89% and 69%, respectively, CRP 75% and 86%, respectively, and PCT 86% and 63%, respectively. It was found that PCT is highly significant predictor of the disease outcome (p < 0,001). Conclusion. In early assessment of AP severity, PCT has better predictive value than CRP, and similar to the APACHE II score. APACHE II score is a stronger predictor of the disease severity than BISAP score. PCT is a good predictor of AP outcome.