CD73 protein, also known as ecto-5′-nucleotidase, is a glycosylphosphatidylinositol (GPI)-anchored cell surface enzyme that catalyzes the hydrolysis of adenosine monophosphate (AMP) to adenosine (ADO). This enzyme plays a crucial role in the suppression of anti-tumor immune responses and promotes tumor progression by generating immunosuppressive adenosine. CD73 is widely expressed in various cell types, including lymphocytes, endothelial cells, epithelial cells, fibroblasts, and neural glial cells, and its expression is significantly influenced by hypoxia and inflammatory factors. During inflammation, CD73 protects endothelial barrier function and inhibits leukocyte trafficking, while also promoting the development of M2 macrophages, which have an anti-inflammatory phenotype. In cancer, CD73 is overexpressed in many tumors and is associated with tumor growth, metastasis, angiogenesis, poor prognosis, and resistance to chemotherapy, making it a promising prognostic indicator and therapeutic target. Additionally, CD73 can function as a cell adhesion molecule and a receptor for extracellular matrix molecules, playing roles in epithelial ion exchange, liquid transport, and tissue barrier maintenance.