BACKGROUND: The prevalence of coarctation of the aorta is 4/10,000, accounting for 8% of congenital heart diseases. Accurate prenatal diagnosis of coarctation of the aorta is still difficult. CASE PRESENTATION: This article tracks and reports two cases of false coarctation of the aorta diagnosed by different hospitals until their postnatal outcomes. It discusses in detail the possible causes of misdiagnosis during prenatal care. It provides an in-depth analysis of the differential diagnosis between redundant foramen ovale flap and coarctation of the aorta. CONCLUSIONS: Assist in prenatal diagnosis of coarctation of the aorta.