(1) Through multivariate analysis, sensitivity analysis, and adjusting the potential confounding factors, this study got a more consistent conclusion: The higher the serum ALB, the better the prognosis of patients with AKI and treated with CRRT; (2) This study also made it clear that increasing the serum ALB might improve the clearance efficiency of serum phosphorus, and then improve the prognosis of critically ill patients with AKI and treated with CRRT. This evidence concerns the gene ALB and acute kidney injury.