ABSTRACT The ductus arteriosus aneurysm (DAA) is considered a rare anatomical alteration that consists of a dilation of this vascular structure. It has been reported that the DAA can resolve in the immediate postnatal stage and do not generate any consequences for the neonate. However, have been described some cases in which the DAA is complicated due to thromboembolic events, rupture of the lesion, respiratory symptoms, and even death. We present a case report of aneurysm of the ductus arteriosus diagnosed at 24 weeks of gestation with detailed imaging study. Also, we highlight the importance of the use of fundamental tools in the diagnosis: 3D ultrasound, multiplanar reconstruction, spatio‐temporal image correlation (STIC), and omniview.