Although cancer has been the leading cause of death in Japan since 1981, advances in early cancer detection combined with aggressive multimodal treatments such as surgical procedures, chemotherapy, and radiotherapy dramatically changed life expectancy of cancer patients. This situation is forcing medical professionals to consider quality of life issues of cancer patients. Because cancer patients often develop functional deficits not only by the cancer itself but also by its treatment and immobility, they need rehabilitation approaches to regain premorbid functional status. Cancer rehabilitation is defined as a comprehensive, multidisciplinary approach to help patients to obtain maximum physical, social, psychological, and vocational functioning within the limits imposed by the cancer and its treatment. The goals of cancer rehabilitation depends on what adaptation may be necessary for the patient to meet physical and personal needs, that is preventive, restorative, supportive, and palliative needs. In addition to direct cancer infiltration and compression to neuro-motor organs, its neuromuscular remote effects and metastatic brain and bone lesions cause various physical dysfunction. Surgical treatment, side effect of chemotherapy and radiotherapy, pain and immobility also affect patient's cognitive, psychological, physical, and nutritional conditions. Physical impairments and disabilities of the cancer patient are so complex that physiatrists should evaluate patient's dysfunction appropriately and set rehabilitation goals realistically. It is required for physiatrists who manage cancer rehabilitation to resolve medical problems, to make strong doctor-patient relationship, and to communicate with other physicians and rehabilitation specialists. Although there are many articles domestically and internationally that cancer rehabilitation is effective for patients to improve functional abilities and quality of life, very few controlled studies are available yet, which makes cancer rehabilitation still controversial and skeptical. Evidence based outcome research as well as cost-effectiveness analyses regarding cancer rehabilitation should be done in the future.