Cancer is a chronic disease that may occur in both children and adults. Occupational therapy focuses on the activity limitations and participation problems in their life. Oncology rehabilitation involves in helping an individual with cancer to regain maximum physical, psychological, cognitive, social, and vocational functioning with the limits up to disease and its treatments in an interdisciplinary team concept. These treatment options are associated with the risk of some side effects, including fatigue, pain, cognitive problems, decrease in bone density and muscle endurance, weight loss, and stress-or anxiety-related psychosocial problems. Occupational therapy approaches are a holistic view in a client center and use training in activities of daily living, assistive technology, education of energy conservation techniques, and management of treatment-related problems, such as pain, fatigue, and nausea. In palliative and hospice care, occupational therapists support clients with cancer by minimizing the secondary symptoms related to cancer and its treatments. At the end of life, occupational therapy offers to identify the roles and activities that are meaningful and purposeful to the client with cancer and try to determine the barriers that limit their performance. Clients with cancer who have childhood cancer or adult cancer can face problems about body structure and functions, activity, and participation, which may limit their participation to their daily life.