TGF-${eta}$ pathway is being extensively evaluated as a potential therapeutic target. The transforming growth factor-${eta}$ (TGF-${eta}$) signaling pathway has the dual role in both tumor suppression and tumor promotion. To design cancer therapeutics successfully, it is important to understand TGF-${eta}$ related functional contexts. This review discusses the molecular mechanism of the TGF-${eta}$ pathway and describes the different ways of tumor suppression and promotion by TGF-${eta}$. In the last part of the review, the data on targeting TGF-${eta}$ pathway for cancer treatment is assessed. The TGF-${eta}$ inhibitors in pre-clinical studies, and Phase I and II clinical trials are updated.