Four hundred and forty-four high-risk oncology patients with malnutrition participated in this study aimed at assessing the effectiveness of nutrition education on improving an oncology patient's dietary intake. We used a nutritional risk screening to select oncology patients in need of nutritional care. Team Nutrition provides technical assistance for foodservice, nutrition education for patients and their caregivers, and support for healthy eating and physical activity to improve their diets and their lives. The average contribution of protein and total energy of each patient increased after imparting the nutritional education to them. Thus, nutritional education is an effective measure to bring about a favorable and significant change in oncology patients' nutrient intake.