N-acetyl-seryl-aspartly-lysyl-proline （AcSDKP）is a kind of anti- fibrosis effects of short peptides, which is normally present in human plasma and circulating mononuclear cells. Recent studies found that AcSDKP was involved in some organ’s fibrosis, such as heart, lung, kidney and liver. AcSDKP could inhibit the target cells such as cardiac fibroblasts, lung fibroblasts, glomerular mesangial cells and hepatic stellate cells proliferation and collagen synthesis and expression. Through a variety of mechanisms including extracellular signal transduction AcSDKP can inhibit a target organ within the collagen deposition and reduce the causative factors leading to organ fibrosis.