In clinical liver transplantation practice, particularly when dealing with low body weight recipients, the limited availability of size-matched donor grafts often necessitates the use of relatively large grafts to complete the transplantation. However, such graft-to-recipient size mismatch significantly increases the risk of developing large-for-size syndrome (LFSS) after liver transplantation. LFSS refers to a spectrum of complications resulting from excessive graft volume or thickness, leading to intra-abdominal compartmentalization, portal venous inflow restriction, hepatic venous outflow obstruction, and impaired graft function. It is especially prevalent in infant recipients, where management is more complex and associated with higher complication rates. To guide accurate clinical recognition, effective prevention, and standardized intervention of LFSS, the Liver Transplantation Group, Branch of Organ Transplant of the Chinese Medical Association and the Branch of Organ Transplant Physicians of the Chinese Medical Doctor Association convened national experts to develop the Chinese clinical practice guideline for prevention and treatment of large-for-size syndrome in liver transplantation (2025 edition), based on a comprehensive review of international and domestic research advances. The guideline adopts the 2009 Oxford Centre for Evidence-Based Medicine levels of evidence system and provides structured recommendations covering the definition and clinical manifestations of LFSS, key assessment parameters, surgical preventive strategies, postoperative monitoring, and multidisciplinary interventions. Emphasizing a "prevention-focused, intervention-supported" therapeutic principle, the guideline advocates for individualized graft-recipient matching and refined surgical techniques. Its implementation aims to standardize LFSS clinical management, enhance the overall safety and success rate of liver transplantation in China, and promote high-quality development of both adult and pediatric liver transplant techniques.