Abstract Background The traditional approach for adult congenital heart disease combined with valvular disease is surgical treatment under cardiopulmonary bypass (CPB). This approach has a high incidence of postoperative complications, especially in patients with pulmonary hypertension and old age. We present two patients in whom the hybrid procedure was used to treat congenital malformations, followed by valve formation and replacement surgery. Case presentation A 63-year-old man had a muscular ventricular septal defect complicated by mitral regurgitation and a 57-year-old man had patent ductus arteriosus complicated by aortic stenosis. In both of the patients, the congenital malformation was successfully treated by the hybrid procedure, followed by valve repair or replacement. Both patients had no complications. A post-procedure echocardiogram showed no residual shunt across the duct. Conclusions Our findings suggest that the hybrid procedure is a useful alternative for treating adult congenital heart disease with valvular heart disease. This procedure reduces the surgical incision and difficulty of surgery, shortens the CPB time, avoids residual leakage after surgery, and reduces recovery and hospitalization times.