Activities of daily living（ADL） is a basic ability for individuals to maintain daily life. Patients with severe diseases are usually dependent on ADL. In addition，due to the influence of post- intensive care syndrome，patients may experience long-term deterioration of ADL and continuous influence on the quality of life of patients after transferring out of ICU. This paper reviews the concept of ADL，the status of ADL of critically ill patients，influencing factors and improvement measures，and puts forward the shortcomings and suggestions in current research，aiming to provide reference for improving the ADL of critically ill patients and improving their long-term quality of life.