The presence of a small aortic annulus creates a difficult technical problem. Whenever possible, the smaller prosthesis of any type should be avoided. A case of aortic stenoinsufficiency with fibrous small aortic annulus [17 mm] in 26 years old adult woman patient was successful operated upon with aortic valve replacement [21 mm St. Jude Medical valve] and enlargement of aortic annulus with Gore-Tex patch. The postoperative course was uneventful.