: Double orifice mitral valve (DOMV) is a rare congenital malformation of the mitral apparatus frequently associated with other congenital malformations of the heart, whereas the isolated form is rare. The prevalence is about 1% of congenital heart disease; valve stenosis and regurgitation are common findings. Echocardiography represents the best method to diagnose DOMV, providing both anatomical and functional data. We report a case of a young woman presenting with an isolated DOMV, in the absence of stenosis and significant regurgitation. The dysmorphic valve has been evaluated with both two-dimensional and three-dimensional echocardiography, providing impressive and detailed images of the peculiar anatomical configuration of the valve.