Acute kidney injury is one of the most intriguing challenges of medicine, as it is followed by high mortality despite progress in understanding and treating the condition. Elderly patients form an especially sensitive group, due to the complications that come with age and various comorbid conditions. The aim of the study was to analyse the outcome of patients on CRRT, specifically mortality, loss or recovery of kidney functions, along with parameters which could have an effect on outcome and which could be improved during therapy for a better outcome. The study included all patients that were treated for acute kidney injury at the Clinical Hospital Centre Rijeka in the last 5 years. Total number of patients was 178, of which 64 were female, and 114 were male. Average age was 74,35 ± 5,46 (65-89). All analyzed patients were treated with continuous renal replacement therapy. Patients were divided into three groups in relation to the outcome (group that passed away, group with the loss and group with the recovery of kidney function). The most common indications for continuous renal replacement therapy were of cardiogenic (n=89, 50,0%) and infectious etiology (n=52, 29,2%). Mortality in patients with acute kidney injury that were treated with continuous renal replacement therapy in our study was 70,8% (n=126), while recovery of renal function occurred in 6,2% (n=11) of the patients. Permanent loss of renal function was more common than recovery, and it occurred in 23,0% (n=41) of the patients. Analysis of parameters revealed that initial creatinine levels, 24-hour diuresis, glomerular filtration, potassium levels and multiple organ failure can be predictors of acute kidney injury outcome in elderly patients