Abstract: TGF-beta(transforming growth factor-beta) is a multifunctional cytokine that regulates growth and differentiation of various types of cells. There are 3 subtypes of TGF- beta receptor, including TβR-Ⅰ, TβR-Ⅱ and TβR-Ⅲ. TGF- beta binds to TβR-Ⅰand TβR-Ⅱ (serine/threonine kinase receptors), which mediates intracellular signals through Smad proteins. Recent findings demonstrate that the TGF-beta and its receptor are associated with tumor. Somatic mutations of TβR have been demonstrated in several different tumor types, including colorectal cancers and pancreatic cancers. The effect of TGF-beta in tumor is complex, TGF-beta is considered as a tumor suppressor gene in early tumor and growth inhibition by the TGF-beta has been extensively studied in many cell types. However, TGF-beta can enhance growth in progressive tumor and possible mechanisms for these growth enhancing effects, including the induced immunosuppression, enhanced angiogenesis, and increased peritumoral stroma formation.