Transforming growth factor-β (TGF-β) signaling is initiated by the activation of transmembrane TGF-β receptors (TGFBRs), which recruit Smad2/3 transcription factors to regulate cellular responses. Dysregulation of TGF-β signaling leads to pathological conditions such as fibrosis, cancer, and inflammation. TGF-β signaling is regulated at multiple levels, beginning with the release of TGF-β from its latent form. The activation of TGFBRs is highly selective, depending on cell type, agonists, and TGF-β isoforms, enabling precise control of TGF-β signals. Various mechanisms, including thrombospondins, integrins, matrix metalloproteinases, and reactive oxygen species, are involved in the release of active TGF-β. Additionally, other signaling pathways can transactivate TGFBRs, leading to the release of active TGF-β and activation of TGFBR signaling. The unique combination of these mechanisms allows for targeted therapeutic approaches to inhibit TGF-β signals. This review highlights the diverse mechanisms underlying TGFBR activation, providing insights into potential therapeutic strategies. TGF-β signaling is regulated by various factors, including integrins, MMPs, and ROS, which can either release active TGF-β or inhibit its signaling. TGF-β signaling is also influenced by other signaling pathways, such as GPCR and TLR4, which can transactivate TGFBRs. Therapeutic approaches targeting TGFBR activation include inhibitors such as vactosertib, galunisertib, and LY2109761, which have shown promise in treating fibrotic diseases and cancers. However, some inhibitors may have cardiotoxic effects, necessitating careful evaluation. Targeting the interaction between TGF-β and TGFBR in the extracellular domain has also been explored as a therapeutic strategy, with examples such as P144 and RER. Additionally, fusion proteins and antibodies targeting TGFBR activation have been developed to enhance therapeutic outcomes. Overall, understanding the mechanisms of TGFBR activation is crucial for developing effective therapies targeting TGF-β signaling in various diseases.Transforming growth factor-β (TGF-β) signaling is initiated by the activation of transmembrane TGF-β receptors (TGFBRs), which recruit Smad2/3 transcription factors to regulate cellular responses. Dysregulation of TGF-β signaling leads to pathological conditions such as fibrosis, cancer, and inflammation. TGF-β signaling is regulated at multiple levels, beginning with the release of TGF-β from its latent form. The activation of TGFBRs is highly selective, depending on cell type, agonists, and TGF-β isoforms, enabling precise control of TGF-β signals. Various mechanisms, including thrombospondins, integrins, matrix metalloproteinases, and reactive oxygen species, are involved in the release of active TGF-β. Additionally, other signaling pathways can transactivate TGFBRs, leading to the release of active TGF-β and activation of TGFBR signaling. The unique combination of these mechanisms allows for targeted therapeutic approaches to inhibit TGF-β signals. This review highlights the diverse mechanisms underlying TGFBR activation, providing insights into potential therapeutic strategies. TGF-β signaling is regulated by various factors, including integrins, MMPs, and ROS, which can either release active TGF-β or inhibit its signaling. TGF-β signaling is also influenced by other signaling pathways, such as GPCR and TLR4, which can transactivate TGFBRs. Therapeutic approaches targeting TGFBR activation include inhibitors such as vactosertib, galunisertib, and LY2109761, which have shown promise in treating fibrotic diseases and cancers. However, some inhibitors may have cardiotoxic effects, necessitating careful evaluation. Targeting the interaction between TGF-β and TGFBR in the extracellular domain has also been explored as a therapeutic strategy, with examples such as P144 and RER. Additionally, fusion proteins and antibodies targeting TGFBR activation have been developed to enhance therapeutic outcomes. Overall, understanding the mechanisms of TGFBR activation is crucial for developing effective therapies targeting TGF-β signaling in various diseases.