Objective To summarize our experience in treating the elderly patients suffering from critical acute lower extremity arterial embolism (CALEAE) and determine the role of continuous veno-venous haemodiafiltration (CVVHD) in improving the prognosis of these patients after arterial embolectomy. Methods Clinical data of 47 elderly patients suffering from CALEAE admitted in our department from June 2008 to May 2015 were collected in this study. According to the intentions of the patients or their families for taking CVVHD, they were divided into treatment group (n＝21) and control group (n＝26). Their clinical data, length of stay, hospital mortality, especially postoperative renal function were compared between the 2 groups. Results There were more patients having peripheral cyanosis and muscle stiffness in the treatment group vs the control group before embolectomy (P＜0.05). The times of the serum levels of potassium, creatinine and urea nitrogen recovering to normal levels were significantly shorter in the patients of the treatment group than in the control group (P＜0.05). The treatment group had remarkably shorter length of stay [(13.5±1.6) vs (18.2±2.1)d, P＝0.043] and lower hospital mortality (9.5% vs 19.2%, P＝0.027). Conclusion CVVHD can shorten the recovery duration, obviously reduce the mortality and length of stay, and improve the prognosis for the elderly patients suffering from CALEAE after operation.