Abstract: Chronic graft-versus-host disease (cGVHD) is the most common late complication after allogeneic hematopoietic stem cell transplantation, with an incidence rate of 30% to 70%. It significantly affects the long-term survival of patients. The clinical manifestations of this disease are highly heterogeneous and can involve multiple organs such as the skin, mouth, eyes, lungs and liver. Its core mechanism involves chronic inflammation, disruption of immune tolerance and dysregulation of T and B cells, ultimately leading to tissue fibrosis. In recent years, with the deepening of research on the pathogenesis, the treatment of cGVHD has evolved from traditional glucocorticoids to targeted drugs targeting key signaling pathways such as JAK, ROCK2 and BTK, biological agents that deplete pathogenic immune cells, and cell therapies for reestablishing immune tolerance, forming a diversified and precise treatment landscape. This article reviews the progress in the epidemiology, pathogenesis, diagnostic assessment and treatment strategies of cGVHD. Current evidence suggests that combined and sequential treatment targeting fibrosis and immune tolerance is a key direction for breaking through the current treatment bottleneck of cGVHD.