The diagnosis of bicuspid pulmonary valve is usually established postmortem, occurring in 7% of patients with pulmonary stenosis and is usually associated to tetralogy of Fallot or ventricular septal defect. The authors report the case of a 14-year-old girl with patent ductus arteriosus in whom 2-D echocardiography disclosed a pulmonary valve formed of two slightly thickened leaflets that opened with the shape of a dome in systole, and moved under the valve ring plane during diastole. A Doppler examination showed a 21 mmHg transvalvar gradient. These characteristic features suggest that 2-D and Doppler echocardiography are the techniques of choice in the diagnosis of bicuspid pulmonary valve.