Objective:To investigate the relation between the dynamic change of N-terminal proBNP(Brain Natriuretic Peptide) and the complic myocardial injury in patients with multiple injury at the early stage,and assess the evaluation value of injury severity. Methods:Fifteen hospitalized patients with multiple injury were collected from Aug 2005 to Apr 2007. All patients were divided into two groups:serious injury group(≥15 point) and control group(<15 point) according to APACHEⅡ scores. Plasma NT-proBNP and cTnI were detected at the 1st,3rd,5th,7th day after admission. Results:There was a positive correlation between plasma NT-proBNP levels and APACHEⅡ scores at the 1st day in patients with multiple injury(r = 0. 601,P < 0.001). The difference of NT-proBNP and cTnI between the two groups was statistically significant in the 1st,3rd,5th,7th day, respectively. The levels of the two indexes in the serious injury group increased more striking than the control group(P < 0.01). The mean values of plasma NT-proBNP and cTnI both increased from the 1st day in two groups. In control group,the peaks of the mean values of plasma NT-proBNP and cTnI appeared at the 3rd day, then decented sequentially,and finally dropped back into the normal range at the 5th day. In serious injury group,the plasma level of NT-proBNP increased consistently until the 7th day,and the peak value appeared latter than the control group(at the 5th day). But the value did not drop back into the normal range at the 7th day. Conclusion:The dynamic change of NT-proBNP in patients with multiple injury may be related to myocardial injury,but serious injury patients may be influenced by many factors. NT-proBNP could be used in evaluation of injury severity at the early stage after trauma.