Cancer cachexia is a multifactorial syndrome characterized by persistent skeletal muscle loss, with or without fat loss, which cannot be completely reversed by traditional nutritional support and leads to impaired organ function. Cachexia seriously reduces the quality of life of (QOL) patients, affects the therapeutic effect against cancers, increases the incidence of complications, and is an important cause of death for patients with advanced cancers. To date, no effective medical intervention has completely reversed cachexia, and no medication has been agreed upon. Here, we describe recent advances in the diagnosis, molecular mechanism and treatment of cancer-related cachexia.