Introduction: The aim of the study is to present a rare mitral congenital malformation – double mitral orifice, characterized by a unique fibrous annulus with 2 orifices that open into the left ventricle. The subvalvular structures may present various degrees of anomalies, specially the tensor apparatus. The mitral inflow may be normal, stenotic or insufficient. Methods: We present 2 cases of double mitral orifice, both males. In both patients an ECG, echocardiography and thoracic X-ray was done. In the 1st case, the disease started at 3 weeks after birth with pulmonary edema, hepatomegaly and hepatic cytolysis. The echocardiography showed a double mitral orifice with a larger anterior orifice and a smaller posterior, with grade III mitral insufficiency, which was reduced after diuretic treatment. The 2nd is a 3 year old boy, admitted in the hospital for irritative persistent cough since 6 weeks. A simultaneous systolic murmur was the reason for an echocardiography and a double mitral orifice with 2nd degree mitral insufficiency with pulmonary stasis was detected. Results: After diuretic treatment the evolution was good. They both need further monitoring to assess possible augmentation of the mitral regurgitation or even stenosis. Conclusions: The literature describes by now around 180 cases. We considered important to present this rare malformation which can be easily missed in neonates.