Most of the reports shows that Acute kidney injury occur in >30% of individuals who undergone cardiac surgery. The risk factors associated with on-pump coronary artery bypass grafting and acute kidney injury requiring continuous renal replacement therapy. The protocol “Off-pump coronary artery bypass surgery” is a form of coronary artery bypass graft in short ‘CABG’ surgery performed without cardiopulmonary bypass in treatment for coronary heart disease. coronary artery bypass grafting without the use of cardiopulmonary bypass or cardioplegia (CABG, or OPCAB) is superior to that performed with the heart-lung machine and the heart’s being chemically arrested (standard CABG).The identification of risk factors for Acute kidney injury in patients after OPCABG may result in better care, more appropriate resource utilization, and, finally, better outcome. Studies were conducted to determine the risk factors that predict acute kidney injury requiring CRRT after bypass surgery. In conclusion, it is possible that the risk of developing acute kidney injury requiring CRRT after OPCABG depended on the levels of glomerular filtration rate, serum albumin and hemoglobin before surgery.