Objective: The aim of this study was to determine selenium levels in cirrhotic patients and to investigate whether the existence of spontaneous bacterial peritonitis (SBP) and the degree of liver cirrhosis had an effect on serum and ascitic fluid selenium (Se) levels in cirrhotic patients. Material: Serum and ascitic fluid selenium levels were studied in 32 cirrhotic patients and 10 healthy controls. Patients were divided into 4 groups. Control subjects (group I, n = 10), patients with compensated cirrhosis (group II, n = 16), patients with massive ascites (group III, n = 14), patients with massive ascites and spontaneous bacterial peritonitis (SBP) (group IV, n = 13). Method: Serum selenium was analyzed by atomic absorption spectrophotometry using an Unicam 939 AA Spectrometer. equipped with Unicam VP 90 vapor system. Results: All cirrhotic patients (groups II, III, IV) showed significant decrease in serum selenium levels in comparison with that in control subject (group I) (p < 0.05). Although serum selenium levels were higher (group II: 46 +/- 16.0 ng/ml) in patients with compensated cirrhosis when compared with other cirrhotic patients (group III: 42.9 +/- 11.0 ng/ml., group IV: 38.4 +/- 6.6 ng/ml), they were not statistically significant (p > 0.05). Ascitic fluid selenium levels were not different between decompensated cirrhotic patients with or without SBP (group III: 10.9 +/- 5.4 ng/ml, group IV: 14.9 +/- 7.3 ng/ml) (p > 0.05). Conclusion: Our findings suggest that decreased Serum selenium levels in cirrhotic patients are not related to the degree of liver cirrhosis and spontaneous bacterial peritonitis.