Abstract: The incidence of cancer has remained high in recent years, and anti-tumor treatment methods are emerging. Cancer treatment has undergone significant changes, and the survival rate of patients with cancer has significantly improved. Various types of new anti-tumor treatments may not only treat and control tumor growth but also place patients in critical situations that require treatment by intensive care medical personnel. Patients with cancer are in critical condition mainly due to three reasons: severe cases caused by cancer diseases themselves, complications during the perioperative period, and accompanying diseases and hospital acquired diseases. In the new situation, we should consider patient characteristics, such as abnormal metabolism, abnormal coagulation system, and abnormal immune mechanism, to save them from serious illness. We need to comprehensively evaluate patients with cancer, emphasize the role of the Intensive Care Unit (ICU) treatment platform, and promote the treatment concept of planned transfer to ICU, to improve the success rate and efficiency of treatment. After transferring the patient out of the ICU, the planned follow-up anti-tumor treatment can still be continued as the endpoint of ICU treatment for critically ill patients with cancer. In the future, efforts will be devoted to establishing a discipline and talent echelon with distinctive characteristics of oncology critical care medicine and treating "the critical illness of cancer and the cancer of critical illness".