We experienced two patients of valvular heart disease associated with Behçet's disease. First patient presented aortic regurgitation (AR) due to perforation of left coronary cusp of the aortic valve and underwent valve replacement (AVR). Second patient showed AR due to shortening of the aortic valve along with mitral regurgitation caused by dilatation of the annulus, and received AVR as well as mitral annuloplasty by Kay's method. Each patient has been doing well for 5 and 2 years after operation, respectively. Patients with Behçet's disease often have perivalvular leakage after valve replacement. We treated our patients as follows to prevent this serious postoperative complication. 1. The operation was performed when the inflammatory signs and findings subsided with enough adrenal steroids. 2. At operation, the prosthetic valve of one size smaller than the size considered suitable was selected for valve replacement. 3. The adrenal steroids have been continuously administrated and adjusted according to the values of CRP and ESR as well as the cutaneous and mucous manifestations of this disease.