Ellis-van Creveld syndrome (chondroectodermal dysplasia) is a rare autosomal recessive disorder characterized by a narrow thorax with short ribs, short extremities with polydactyly, and heart defects. A woman underwent sonographic examination at 27 weeks' menstrual age to rule out anomalies because of premature labor. Sonography revealed a live fetus with short long bones, polydactyly in the hands and feet, a narrow thorax with short ribs, and an atrial septal defect. All bony structures were of normal hyperechogenicity. The placenta appeared normal and was located at the posterior uterine wall; the amniotic fluid volume was also normal. These findings led to the diagnosis of short-rib dysplasia, most likely Ellis-van Creveld syndrome. The preterm labor stopped but spontaneously recurred at 35 weeks, when a 2,320-g female infant was vaginally delivered. The infant died of pulmonary insufficiency shortly after birth. Postmortem examination confirmed the prenatal findings. We conclude that Ellis-van Creveld syndrome can be readily diagnosed by prenatal sonography in the third trimester.