Abstract: Arginine, a semi-essential amino acid, is crucial for cells to maintain normal life activities. Arginine not only participates in multiple metabolic pathways within cells as a substrate but also directly participates in regulating the process of cell signaling transduction as a signaling molecule. Compared with normal cells, tumor cells often reshape the arginine metabolism to meet their own needs for rapid proliferation. Currently, the anti-tumor strategy targeting arginine metabolism has entered the clinical stage of research. Recent studies have shown that arginine plays an important role in various immune cells within the tumor microenvironment, which has opened up new research directions for tumor treatment strategies targeting arginine metabolism. This article reviews the functions of arginine as a metabolite and signaling molecule, with focus on the regulatory effects and internal mechanisms of arginine metabolism on tumor cells and the tumor immune microenvironment, and at the same time expounds the latest progress of tumor treatment by targeting arginine metabolism, aiming to provide robust theoretical support for anti-tumor strategy targeting arginine metabolism.