【Abstract】Objective To evaluate predictive value of N-terminal pro-B-type natriuretie peptide(NT-proBNP) on the prognosis of critically ill patients in surgical intensive care unit and its possible influential factors. Methods The level of NT-proBNP in blood was measured and the clinical data was collected in 136 critically ill patients who were admitted in SICU. The patients were divided into death group and survival group according to 30-day mortality．The level of NT-proBNP was compared between death group and survival group and analyzed with the clinical factors by multiple regression analysis. Results There was statistically different in NT-proBNP between the death group (3.24±0.60) and survival group group (2.93±0.65) (P = 0.021). Multiple regression analysis showed that NYHA classification of cardiac function, age, and renal function were significantly related to NT-proBNP, but gender, hemoglobin, acute physiology and chronic healthy evaluation Ⅱscore （APACHⅡ）, surgical approach, and the state of sepsis or hypertension in the multiple regression analysis did not showed any significant. Conclusions The level of NT-proBNP had a good predictive value on the prognosis of critically ill patients in SICU, and was significantly associated with NYHA classification of cardiac function, age, renal function. So these factors should be taken into account when NT-proBNP was used to predict the prognosis of the critically ill patients.