The evaluation of physical functioning is important in the intensive care unit to identify patients at risk of poor physical outcomes, monitor intervention efficacy, and inform recovery trajectories. So far various functional evaluation tools for Intensive care unit patients have been developed but there are no agreed standardized measurement tools yet. This study discusses that the clinical utility and practical considerations of functional evaluation tools in the intensive care unit (ICU) setting and made recommendations for clinical practice. Although most evaluation tools show excellent reliability, each tool has a different method of use and range for score depending on the measurement items. So, it is necessary to measure early and longitudinally the ICU patient’s physical function from the beginning of hospitalization to postdischarge of ICU by selecting an evaluation tool suitable for medical fee and ICU setting in Korea.