Cross-sectional echocardiography has enabled us to demonstrate foetal cardiac structures, however, only a few studies have been reported. This report deals with a recently experienced foetus with double outlet right ventricle )DORV) diagnosed by this technique, confirmed by angiography and autopsy after birth. A 24-year-old pregnant woman with 24 weeks foetus underwent echocardiographic studies to evaluate the foetal heart because of its bradycardia. The cross-sectional echocardiogram showed a quite abnormal finding; i.e., two great arteries arose from the single ventricle which had coarse trabeculations. This finding suggested either DORV or single ventricle. The foetus was born at 40 weeks as a girl weighted 3040 g, and cyanosis was not observed. At one month of age, she began to experience increasing cyanosis by crying, and admitted to Keio Hospital for further examinations. She was performed catheterization and angiography, and was diagnosed as DORV. Cyanosis and dyspnea developed gradually and she died at the age of 2 months. Autopsy revealed DORV, polysplenia and dextrocardia.