The present invention provides a medical use of fimbrin T (Plastin 3, PLS3) thiol nitrosation modification and relates to the cardiovascular field; Plastin 3 thiol nitrosylation modification level invascular tissue of human aortic dissection is increased; at a cell level, Ang II induces modification of the PLS3 in endothelial cells and the modification site is at position 566 of cysteine; and atan animal level, an aortic dissection model is constructed by BAPN and endothelial cell-specific overexpressed PLS3-C566A relieves formation of the arterial dissection and improves aortic diastolic functions of mice in the model. The present invention provides the application of the fimbrin T in preparation of medicines for treating the aortic dissection endothelial dysfunctions and particularly an application of a biological carrier inhibiting the fimbrin T cysteine 566 thiol nitrosylation modification level in preparation of medicines for treating the aortic dissection vascular endothelial dysfunctions. The medical use of the fimbrin T thiol nitrosation modification opens up the new medicine application for the aortic dissection vascular dysfunctions and provides meaningful reference toresearch and development of the aortic dissection vascular dysfunctions.