Background: A common bacterial infection of ascitic fluid in ascites due to liver cirrhosis is spontaneous bacterial peritonitis. Human neutrophil granules release a 24 KDA glycoprotein called neutrophil gelatinase associated lipocalin (NGAL). (NGAL) is a tissue injury and infection marker. Aim: The aim of this study was to determine the amount of NGAL in ascitic fluid in patients with liver cirrhosis and spontaneous bacterial peritonitis. Methodologies: A total of 85 patients with cirrhotic ascites were included in the study. 42 of them had SBP. The severity of liver cirrhosis was assessed using the Child-Pugh score, the Model for End Stage Liver Disease (MELD), and its update (uMELD) scores. Ascitic fluid samples were collected for leucocytic count differentiation, albumin, protein, glucose estimation, and the serum-ascetic albumin gradient. Both patients had their NGAL levels measured in their ascitic fluid. If the polymorph-nuclear leucocytic count in ascitic fluid was more than 250/mm 3 , SBP was diagnosed. Results: The level of NGAL in ascitic fluid was significantly higher in patients with SBP. ROC analysis of ascitic NGAL as a marker for SBP diagnosis revealed: sensitivity of 97.62 percent, specificity of 97.67 percent, and area under curve (AUC) of 0.974 at a cut-off value of 100.8 (ng/dl). White blood cells, polymorph nuclear cells (PNCs) in ascitic fluid, Child Pugh score, MELD score and uMELD score all had a negative correlation with NGAL in non SBP group. Conclusion: In patients with spontaneous bacterial peritonitis, ascitic fluid NGAL may be a useful diagnostic marker.