Background and study aims: Spontaneous bacterial peritonitis (SBP) is an infectious complication observed in patients with cirrhosis and ascites, representing a manifestation of severe derangement of hepatic functions. The aim of this study was to assess the role of tumour necrosis factor- alpha (TNF-α) and interleukin-6 (IL-6) in hepatic deterioration in cirrhotic patients with SBP . Patients and methods: Twenty eight cirrhotic patients with ascites were divided into two groups: group1(n = 16) , complicated by spontaneous bacterial peritonitis , nine males and seven females, and group II (n = 12) , not complicated by spontaneous bacterial peritonitis used as control, eight males and four females. The mean ages were 56.9 ± 7.4 and 56.2 ± 7.4 years in group I and II respectively. For all patients complete medical history, clinical examination, abdominal ultrasonography, liver function tests, ascitic fluid analysis, serum levels of both TNF-α and IL-6 by enzyme-linked immunosorbent assay (ELISA) were done Results: Serum levels of TNF-α, IL-6, total bilirubin, alanine aminotrarnsferase (ALT), aspartate aminotransferase (AST),prothrombin time, and ascitic total and polymorphnuclear cell counts were significantly higher in group I compared to group II while albumin content of ascitic fluid was significantly lower in group I compared with group II. However, no significant difference was found between two groups as regard total serum protein, serum albumin and total ascitic protein .In addition, there was a significant positive correlation between serum levels of both TNF-α and IL-6, and ALT, AST and prothrombin time . However, there was a significant negative correlation between serum levels of both TNF-α and IL-6, and serum albumin. Furthermore, there was a positive correlation between serum levels of both TNF-α and IL-6 and serum total bilirubin but no statistically significant difference.Conclusion: Serum levels of both TNF-α and IL-6 were higher in cirrhotic patients with SBP than in patients with sterile ascites. The elevation of these parameters were parallel to deterioration of liver functions. Thus , these cytokines could be play a major role in hepatic impairment . further studies needed for clarifying the role of these parameters as a predictor of poor prognosis in cirrhotic patients with SBP.