Head and neck cancer and the approaches used to treat it can cause symptoms such as mucositis, alteration or loss of taste, dysphagia, and xerostomia, which makes the incidence of malnutrition in head and neck cancer patients higher than in the general population of cancer patients. Malnutrition in patients with head and neck cancer is associated with the occurrence of treatment-related adverse events, an increase in overall economic cost, a decline in quality of life, and a poor prognosis. Therefore, rehabilitation interventions for malnutrition are necessary throughout the course of the disease. However, the importance of rehabilitation interventions for malnutrition in patients with head and neck cancer has not been fully recognized, and the optimal methods and timing of interventions are unclear. This article provides an overview of rehabilitation interventions for malnutrition, including nutritional supplementation, exercise-based interventions, nutritional counseling and cognitive improvement, and drug therapy, and discusses their advantages and disadvantages as well as potential future directions.