Sarcopenia as well as cancer cachexia is recognized as a poor prognostic factor for malignant tumors. Sarcopenia predicts poor surgical outcomes, treatment of toxic effects, and reduced survival. Cachexia, which occurs in up to 80% of those with cancer, is a life-threatening condition associated with several pathologies. In colorectal cancer, sarcopenia and cancer cachexia are less common than in other cancer types. However, sarcopenia or cancer cachexia in colorectal cancer has been also reported, suggesting their association with the effects or prognosis, respectively. Sarcopenia and cancer cachexia may coexist, and it is important to recognize them. We report the latest findings on the relationship between colorectal cancer and sarcopenia/cancer cachexia.