Background: In early phase of acute pancreatitis (AP), systemic inflammatory response syndrome may lead to organ failure. The severe form of AP is associated with high mortality that may be prevented by timely diagnosis and treatment of the predicted severe cases. Serum interleukin 6 (IL-6) and urokinase-type plasminogen activator receptor (uPAR) have been proposed as accurate early markers of severe AP. The aim of the study was to assess whether widely available blood count indexes: neutrophil to lymphocyte (NLR), lymphocyte to monocyte (LMR) and platelet to lymphocyte ratios correlate with IL-6 and uPAR and may be utilized to predict organ complications at the early phase of AP. Methods: The study included 95 adult patients with AP treated at the Surgical Ward Complex of Health Care Centers in Wadowice, Poland. Organ failure was diagnosed according to modified Marshall scoring system, as recommended by 2012 Atlanta classification. Blood samples for laboratory tests were collected on days 1, 2 and 3 following the onset of AP symptoms. Results: Patients with organ failure presented significantly lower LMR on day 1 and signifi cantly higher NLR on days 2 and 3. Strong positive correlations between NLR and IL-6 and moderate correlations between NLR and uPAR were observed throughout the study. Day 2 and 3 NLR values significantly predicted organ failure at the early phase of AP. Conclusions: Taking into account the wide availability of NLR, it may be considered as a surrogate of more expensive tests to help the early assessment of organ failure complicating AP.