Decorin (DCN) is a member of the small leucine-rich proteoglycan gene family. Many studies indicated that DCN inhibited fibrosis and scar-formation by neutralization of TGF-P and interfering the binding of TGF-beta with its receptor, which induced ectopic deposition of extracellular matrix. Additionally, DCN can prevent the proliferation and metastasis of tumor cells by activating EGFR/MAPK/p21 signal pathway and inhibiting the cell proliferation pathway mediated by EGF-EGFR. It is suggested that the recombinant DCN had potential pharmaceutical potency in treatment of chronic fibrosis and neoplasm for its critical biological activities and low immunogenicity.