Over the past decades, despite advanced progress in research and medical, acute kidney injury is still associated with significant morbidity and mortality. Traditional diagnostic criteria of acute kidney injury is based on serum creatinine, which is not a reliable indicator during acute changes of kidney function. Novel biomarkers such as NGAL, KIM-1, IL-18 and cystatin C allow us to unravel the complex pathophysiology of acute kidney injury, and more importantly, to provide the chance of early diagnosis and timely treatment.