Patients diagnosed with cancer have a particularly high risk of developing malnutrition due to the disease itself and due to symptoms of cancer treatments that can affect food intake such as reduced appetite, nausea, fatigue, and alterations in taste and smell. Nutritional treatment is essential in the prevention and treatment of malnutrition. Oral nutritional supplements (ONS) are often recommended to cancer patients who need to increase their nutritional intake and are unable to meet their nutritional requirements by consumption of normal food alone. However, patient compliance with ONS depends on sensory acceptability of such products. Therefore, the objective of this study is to investigate preferences of sensory characteristics of ONS among cancer patients. Additionally, possible associations between taste and smell alterations and dietary intake, malnutrition risk, and quality of life will be investigated. The results from this study will optimize recommendations of ONS in the clinical setting and encourage new efforts among manufacturers in developing acceptable sensory characteristics of ONS to cancer patients. Findings from this study will contribute to improving nutritional treatment for cancer patients.