Abstract: The increasing recognition of nutritional science has led to a growing focus on hospitalized patients with pre‑existing malnutrition. However, the issue of nutrition deterioration during hospitalization, particularly hospital‑acquired malnutrition (HAM) in patients who were not malnourished prior to admission, remains frequently overlooked. Numerous factors contribute to HAM in hospitalized patients, adversely influencing treatment decisions and outcomes, elevating the risk of complications, extending hospital stays, and diminishing quality of life, ultimately resulting in a spectrum of unfavorable clinical outcomes. The promotion of comprehensive nutritional manage-ment and the advancement of nutritional technology are essential for the timely identification and assessment of the nutritional status of hospitalized patients. This approach facilitates the implemen-tation of nutritional therapy in a systematic and evidence‑based manner, thereby effectively preven-ting HAM and improving the patient′s clinical outcomes.