Transforming growth factor-β (TGF-β) plays an important role in the development of tissue fibrosis and tumors. The present study intends to analyze its physicochemical properties and molecular structure, which will provide new ideas and basis for further research on the mechanism of action of TGF-β in clinical treatment by providing new targets and life activities. A variety of biology online software was applied to analyze the physicochemical properties, signal peptide structure, transmembrane region, subcellular localization, secondary structure, and to conduct conserved structural domain analysis of TGF-β. The molecular weight of TGF-β is 49 312.95 Da, the protein formula is C2203H3375N629O629S18, and the theoretical isoelectric point is 7.74. And it is a basic and stable hydrophilic protein; the instability index is 53.82, belonging to stable protein; the average hydrophilic value is -0.397, and the fat index is 76.96; TGF-β is a hydrophilic protein, and glycine at the 19th position of the amino acid sequence of TGF-β has the largest hydrophobicity, with the score being 2.167; tyrosine 53th had the highest hydrophilicity, with a score of -3.233. TGF-β is a basic, unstable hydrophobic protein, localized in the extracellular matrix (66.7%), endoplasmic reticulum (22.2%) and vesicles (11.1%), respectively. The secondary structure of TGF-β was mainly composed of random coils (55.81%) with 4 N-glycosylation, 15 O-glycosylation and 32 phosphorylation sites. In addition, TGF-β high expression was closely associated with poor prognosis of tumor. These results will provide a new theoretical basis for studying the function and mechanism of action of TGF-β in life activities.