Sarcopenia is a syndrome characterized by progressive and generalized loss of skeletal muscle mass, loss of muscle strength and/or reduced physical performance. Sarcopenia has repeatedly been reported as a strong predictor of both short- and long-term outcomes following surgical treatment for colorectal cancer. In this study, 86 primary colorectal cancer cases who received surgery at our hospital were examined. To evaluate which factor amongst muscle volume, muscle strength or physical performance would be important to avoid sarcopenia after surgery, we examined objective values of muscle volume, muscle strength and physical performance respectively. We also divided patients into groups by their ages or procedures of surgeries, then compared and analyzed within those groups. The results showed that most patients tended to lose their muscle volume of their legs and their physical performance after their surgeries. We also found patients who were equal or older than 75-year-old and patients who received open surgeries tended to lose their muscle volume or physical performance after their surgeries. These groups of patients have a potential risk to turn sarcopenia after surgeries. It would be important to observe each of 3 factors such as skeletal muscle volume, muscle strength and physical performance to evaluate precisely their condition of sarcopenia. Tailor-made peri-operative rehabilitation programs, especially for elderly patients or patients who received open surgeries, would be a possible solution to avoid sarcopenia after surgery for colorectal cancer.