B-type natriuretic peptide has shown promising results as a biomarker for acute kidney injury in general intensive care patients. It may also indirectly reflect fluid balance of the circulation. Among burn patients, it has been observed to indicate excessive fluid resuscitation and organ dysfunction, although its clinical use to indicate acute kidney injury or guide fluid resuscitation has not been validated. The aim of this study was to evaluate whether the N-terminal pro-brain natriuretic peptide values are related to the amount of fluids given after severe burn injury and whether it can act as a novel biomarker for acute kidney injury in these patients. Nineteen consecutive burn patients were included. Plasma N-terminal pro-brain natriuretic peptide was measured daily during 1 week from admission. Other variables such as laboratory values and intravenous infusions were also recorded. The association between acute kidney injury and N-terminal pro-brain natriuretic peptide values was analyzed with a multivariable panel regression model, adjusted for burned total body surface area, age, body mass index, and laboratory values. N-terminal pro-brain natriuretic peptide values varied between single patients, and even more between the patients who developed acute kidney injury. Older age, lower body mass index, and cumulative infusions were independently associated with higher N-terminal pro-brain natriuretic peptide values, whereas acute kidney injury was not. N-terminal pro-brain natriuretic peptide values correlated with cumulative infusions given during the first week. The authors could not validate the role of N-terminal pro-brain natriuretic peptide as a biomarker for acute kidney injury in burns.