Objective To summarize the prenatal ultrasonic characteristics of unilateral pulmonary artery of ductal origin. Methods Fetal echocardiography data from 4 fetuses with unilateral pulmonary artery of ductal origin were retrospectively analyzed, Neonatal echocardiography, cardiac CTA examination data and autopsy reports of induced infants were followed up, and the prenatal echocardiography characteristics are summarized Results Among the 4 fetuses with unilateral pulmonary artery of ductal origin, there were 3 cases with left aortic arch and right pulmonary artery originating from arterial ducts, and 1 case with right aortic arch and left pulmonary artery originating from arterial ducts; The prenatal pulmonary artery bifurcation view showed only one pulmonary artery ,with the other side absent; The coronal view of the anomalous artery revealed the distal pulmonary artery on the affected side connected to the root of the anomalous artery through arterial duct. 3 cases chose to continue the pregnancy, and postnatal echocardiography did not show the affected pulmonary artery, Cardiac CTA revealed pulmonary artery agenesis and a cystic diverticulum in the root of the unnamed artery; In one case, the pregnancy was terminated, and autopsy findings after induction of labor showed right pulmonary artery connected to the root of the anomalous artery through the arterial duct. Conclusion Prenatal fetal echocardiography can accurately diagnose unilateral pulmonary artery of ductal origin. The ductus arteriosus on the affected side will constrict and become atretic after birth. Prenatal diagnosis holds significant clinical value.