Valvular heart disease is rare in patients with juvenile chronic arthritis. We describe a 27-year-old woman with the systemic-onset form of juvenile chronic arthritis in whom aortic insufficiency necessitated valve replacement. Nodules were seen on both the aortic and anterior mitral leaflets at surgery, and histopathologic evaluation of the excised aortic leaflets demonstrated nonspecific changes similar to those described in rheumatoid valve disease causing aortic insufficiency in adults with rheumatoid arthritis. We believe that this is the first reported case of aortic insufficiency in systemic-onset juvenile chronic arthritis in which the pathologic condition of the valve can be attributed to the underlying disease.