Bilateral pulmonary agenesis (BPA) is a rare pathologic condition characterized by the complete absence of lung tissue. The few cases that have been presented in the literature have emphasized the pathologic features of the condition as seen in gross and microscopic evaluation of the fetus or neonate. This report describes the prenatal sonographic appearance of this rare congenital anomaly. Our report illustrates the need to consider the diagnosis of BPA when a congenital diaphragmatic hernia (CDH) is suspected.