Objective: To investigate the epidemiology of acute kidney injury and to clarify the risk factors associated with the prognosis of acute kidney injury in critically ill patients in the Gansu Province.Methods: This was a multicenter, retrospective study. The clinical data of all patients from January 1, 2017, to December 31, 2019, in the intensive care unit of the selected hospitals were screened. Descriptive statistical analysis was performed first, and then the patients were divided into a survival group and a nonsurvival group based on survival status at discharge. RESULTS: (1) Among the 8106 patients admitted, a total of 3019 patients were excluded according to the exclusion criteria. Among the included patients, 890 patients met the diagnostic criteria for AKI, with an incidence of 17.5% and mortality of 41.3%. Among the selected AKI patients, AKI stage I accounted for 22.02%, AKI stage II accounted for 31.01%, AKI stage III accounted for 46.97%, and 35.8% of the AKI patients received renal replacement therapy. The higher the AKI stage was, the higher the percentage of renal replacement therapy use. (2) Logistic regression analysis showed that sex, age, AKI stage, RRT, infection, cardio-pulmonary resuscitation, cardiac output, mechanical ventilation, diuretics, white blood cells, platelets, blood urea nitrogen, prothrombin time and activated partial thromboplastin time were significantly associated with the prognosis of acute kidney injury (P <0.05). Further analysis showed that male sex, old age, high AKI stage, RRT treatment, low cardiac output, mechanical ventilation, elevated leukocyte count, reduced platelet count and reduced serum albumin were independent risk factors for a poor prognosis of AKI. Conclusions: Data from several representative general hospitals in the Gansu Province showed that the incidence and mortality of acute kidney injury in intensive care units were still very high. Sepsis and septic shock are the main causes of AKI.