Abstract Background: Malnutrition is common among patients with hematologic malignancies, but there are few clinical studies on disease-specific nutritional characteristics and the appropriateness of nutritional support. Methods: This cross-sectional study included 633 hospitalized patients with hematologic malignancies. Nutritional risk was assessed using the NRS-2002, malnutrition was diagnosed according to GLIM criteria, and the appropriateness of nutritional support was evaluated.