The invention relates to application of captopril to the preparation of medicaments for treating and/or inhibiting scar hyperplastic diseases. Particularly, the hyperplastic diseases comprise hyperplastic scar, cheloid, urethral scar stricture and silicon gel breast augmentation prosthesis postoperative capsular contracture. When the diseases are treated, the captopril is used as an active ingredient, clinically-used emulsifiable paste, gel, injection and the like in different formulations are prepared by the conventional preparation process. The study indicates that the captopril can reduce the capacity of synthesizing pathologic scar fibroblast collagen and secreting the collagen, weaken the multiplication capacity of fibroblasts and reduce the expression of transforming growth factor-beta 1 (TGF-beta 1), and has a good treatment or prevention effect on pathologic scars. Simultaneously, the captopril acts on scar tissue directly, has the advantages of small dose, high curative effect, small side effect, mature raw material process, readily available materials, low cost and the like, and is expected to become a main medicament for treating and preventing the scars clinically.