Abstract: Objective To evaluate the value of plasma brain natriuretic peptide （BNP） in evaluating the severity of burn patients. Methods Samples were collected from 72 cases of burn patients in our hospital from February 2015 to March 2016，according to common burn method to divided into mild injury group （n=28，II degree burn area<9%），moderate burn group （n=25，II degree burn area of 10-29%，or III degree burn area<10%） and severe burn group （n=19，total burn area of 30-50%，or III degree burn area of 10% to 20%），about 3 mL of venous blood samples were drawn from the patients with injury after 24 h，48 h，72 h，96 h，respectively，immunefluorescence detection method was used to detect the blood BNP concentration，the expression level. venous blood samples from 20 cases of healthy volunteer （fetch medical examination） in our hospital were drawn as a reference. Results BNP level in 72 cases of burn patients after 24 h，compared with the normal control group，had no significant difference （P>0.05），but injury after 48 h，72 h，96 h blood BNP value were significantly increased，the difference has statistical significance （P<0.05）; BNP value differences in minor burns，moderate burn group and severe burn group after injury in 24 h blood had no statistical significance （P>0.05），but at 48 h，72 h，96 h BNP value，compared to the 24 h，were significantly increased （P<0.05）; correlation analysis showed that the burn severity and plasma levels of BNP were highly positive correlation （r=3.057，P<0.05）. Conclusion The blood BNP of burn patients reflects the characteristics of change with abnormal elevation，and is positively correlated with the degree of burn，which provides an important reference for dynamic assessment of the patient's condition，guiding clinical treatment and so on.

Key words: BNP, Degree of burn , Evaluation