Spontaneous bacterial peritonitis (SBP) is defined as an infection of initially sterile ascitic fluid (AF) without a detectable, surgically treatable source of infection. It is a frequent and severe complication of cirrhotic ascites. Because of the high morbidity and mortality of SBP, the rapid and accurate diagnosis is required. Aim: The present study aimed to measure the levels of tumor necrosis factor-alpha (TNF-alpha), tumor necrosis factor receptor (TNF-r p55) and C-reactive protein (CRP) in both ascetic fluid and serum of patients with sterile and infected cirrhotic ascites to show their diagnostic values as compared to ascitic fluid culture and polymorphnuclear leukocyte (PMN) count. Patients and methods: TNF-alpha, TNF-r p55 and CRP were measured in both ascetic fluid and serum of 20 patients with spontaneous bacterial peritonitis (SBP), in addition to 22 patients with sterile cirrhotic ascites. Results: The results of clinical examination showed a significant difference as regard abdominal pain, fever jaundice, upper GIT bleedings, encephalopathy and Sclerotherapy among both groups. The serum levels of CRP and TNF-alpha were significantly higher in patients with SBP as comparing to patients have sterile ascites, but TNF-r p55 serum level showed no significant difference. On evaluation of ascetic fluid parameters, total leucocytic count (TLC), plymorphnuclear (PMN) count , CRP, TNF-alpha, TNF-r p55 are significantly higher in SBP patient group than group of sterile ascites. Sensitivity and specificity of ascitic fluid PMN (cut-off value >250 cells/ mm3) in discriminating infected ascites from sterile ascites were 70% and 86.4%, respectively. Sensitivity and specificity of ascitic fluid CRP (cut-off value >1.0 mg/dL) in discriminating infected ascites from sterile ascites were 85% and 72.7%, respectively. Sensitivity and specificity of ascitic fluid TNF-alpha (cut off value >12 pg/ml) in discriminating infected ascites from sterile ascites were 80% and 63.6%, respectively. Sensitivity and specificity of TNF-r p55 (cut-off value >6.2 pg/ml) in discriminating infected ascites from sterile ascites were 75% and 68.2%, respectively. Conclusion: We concluded that, the elevated serum and ascetic fluid levels of CRP, TNF-alpha and TNF-r may suggest their role in the pathogenesis of ascetic fluid infection and their higher sensitivity and specificity make them to be good discriminators in ascetic fluid infection (especially a cheap and easy ascitic fluid CRP levels). Thus may help in rapid diagnosis and early start empirical antibiotic therapy without waiting the culture results.