Most acute renal failure of pre-renal and post-renal nature recover without sequelae after prompt treatment. Renal acute renal failure may have sequelae after recovery. Acute renal failure is categorized into pre-renal, renal, and post-renal. Pre-renal factors such as insufficient renal perfusion due to insufficient effective blood volume, and post-renal factors such as bilateral urinary tract obstruction, at this time, if early detection, active diagnosis, treatment, the vast majority of patients renal function can be restored to the baseline level, and usually do not produce sequelae. While the prognosis of renal acute renal failure varies greatly, some patients, especially patients with chronic kidney disease combined with acute kidney injury, the risk of entering end-stage renal disease is greatly increased; if treated reasonably, some patients with chronic kidney disease renal function can be completely or partially recovered. Patients with acute renal failure must seek early medical treatment, early detection and early formal treatment.