Abstract: Epigallocatechin gallate (EGCG), the most abundant catechin in green tea, possesses various biomedical activities and has garnered significant attention because of its notable anticancer properties. This article reviews the research progress on the antitumor mechanisms of EGCG, focusing on its roles in inducing tumor cell apoptosis; inhibiting tumor cell proliferation, angiogenesis, invasion and metastasis; modulating the tumor microenvironment; and influencing epigenetic modifications. Given its natural origin, safety, and low cost, EGCG could be a preferred option for the development of new cancer therapeutic drugs or enhancing the efficacy of combination therapies. This work aims to provide a theoretical foundation for further research and development of EGCG and scientific evidence for its application in cancer prevention and treatment.