To investigate the factors related brain natriuretic peptide (BNP) in patients with early sepsis. Methods Totally 123 patients with sepsis were collected according to the experiment design. The experiment A was designed according to the results of blood culture. The patients with positive boold culture were defined as positive group, and those with negative boold culture were defined as negative group. The experiment B was further designed according to the classification of bacteria. The patients with Gram-negative bacteria infection were taken as Gram-negative group, those with Gram-positive bacteria infection as Grampositive group. In both experiments, age, white blood cells (WBC), C-reactive protein (CRP) and procalcitonin (PCT), APACHE Ⅱscore, left ventricular ejection fraction (LVEF), creatinine, lactate, platelets and BNP were compared between the two groups of patients. Multivariate regression analysis was used to investigate the influences of age, WBC, CRP, PCT, LVEF, APACHE Ⅱscore, serum creatinine, lactate and platelets on BNP in the experiment A. Results The levels of BNP, CRP, WBC, PCT, platelets and lactic acid of the blood culture positive group were significantly higher than those of the blood culture negative group. The APACHE Ⅱscore, BNP, lactic acid and PCT of the Gram-negative group were significantly higher than those of the Gram-positive group. There was no statistical difference in LEVF between the two groups in the experiment A or B. Multiple regression analysis suggested that PCT was the major influencing factor of BNP. Conclusions BNP and cardiac function do not have a correlation in early sepsis patients. PCT is the direct factor contributing to the rise of BNP.