Abstract : The purpose of this study was to predict the outcome of critically ill patients by change of TNF serum level comparing it with q SOFA and APACHE II scores. It included 150 critically ill patients were admitted to Assuit University Hospitals ICUs. All patients underwent carful medical history, clinical examination, abdominal us and ECG. Serum samples were collected for TNF and routine investigations included renal and liver function tests, CBC, ABG, and LDH. There was significant correlation between short term mortality and serum levels of TNF, APACHE II and q SOFA scores as (P were 0.005, 0.01, 0.002 respectively). TNF and q SOFA had significant correlation with Long-term mortality (P were 0.006, 0.001 respectively) but APACHE II had insignificant correlation with Long-term mortality as (P was 0.059). TNF and APACHE II had significant correlation with hospital stay length (P were 0.001, 0.001 respectively) while q SOFA had insignificant correlation with hospital stay length as (P was 0.6). This study concludes that TNF is good predictors for mortality (short and long term) and the duration of hospital stay.