Transforming growth factor-β (TGF-β) is a pleiotropic cytokine which belongs to the TGF-β superfamily that regulates cell growth and differentiation. In the later stages of tumor development, TGF-β may regulate tumor metastasis and recurrence by inducing epithelial-mesenchymal transition, promoting tumor angiogenesis and regulating immunosuppression through autocrine and paracrine effects. Therefore, TGF-β has been implicated as an important factor in the growth, progression, and metastatic potential of advanced cancers. Neutralizing or blocking TGF-β represents a unique method of intervening and disrupting a key promoter of tumor growth and may provide a new therapeutic opportunity. This review discusses the structure, function and mechanism of TGF-β in tumor microenvironment, and lists some drugs targeting TGF-β, aiming to provide reference for the development and clinical application of anti-tumor drugs.