We studied whether N-terminal pro brain natriuretic peptide (NT-pro BNP) measured at intensive care unit admission is an independent predictor of mortality in critically ill patients. We conducted a prospective observational cohort study enrolling 78 patients with APACHE II scores more than 12. Serum NT-pro BNP and cardiac troponin T were measured at admission, and echocardiography was performed within 24 h. The primary end-point was 30-day mortality. The median NT-pro BNP levels of the 22 (28.2%) patients who died were significantly more frequent than that of those who survived (8328 versus 1016 pg/mL; P = 0.001). Patients with NT-pro BNP levels more than 1900 pg/mL had significantly more frequent mortality (47.2% versus 11.9%; P = 0.03). This group also had more frequent moderate to severe left ventricular dysfunction (30.6% versus 9.5%; P = 0.02) and abnormal cardiac troponin T levels (33.3% versus 14.3%; P = 0.05). Multivariate analyses adjusted for APACHE-II revealed that a NT-pro BNP level more than 1900 pg/mL is an independent predictor of mortality.