The effectiveness of many physiological parameters and laboratory tests was investigated in predicting mortality. In this study, we investigated hematocrit, C-reactive protein, transferrin and total lymphocyte count along with Acute Physiology and Chronic Health Evaluation II and Glasgow Coma Scores of patients who were hospitalized in the intensive care unit. The data were retrospectively analyzed from hospital information management system, doctors' records and nurse observing forms. The mortality rate was 42.6%. The Acute Physiology and Chronic Health Evaluation II scores were significantly higher in cases with mortality compared to those without mortality. The admission and discharge Glasgow Coma Scores were significantly lower in patients who showed mortality compared with patients without mortality. Admission and discharge hematocrit and transferrin values were significantly lower in cases with mortality compared to those without mortality. Discharge C-reactive protein values were significantly higher in cases with mortality compared to those without mortality. Discharge total lymphocyte count values were significantly lower in cases with mortality compared to those without mortality. Consequently, we believe that hematocrit and transferrin values at the time of admission to the intensive care unit and total lymphocyte count and C-reactive protein at the time of discharge from the intensive care unit can be effective in predicting mortality.