Trisomy 18 (Edward syndrome) is the second most common chromosomal anomaly of the autosomal trisomy. Prenatal diagnosis of trisomy 18 is extremely important because of the complex malformations and lethal prognosis. Prenatal sonographic findings at 17 weeks of gestation showing radial aplasia with upper limb contracture, omphalocele, and suspicious esophageal atresia suggested the diagnosis and led to amniocentesis. Karyotyping revealed trisomy 18(47 XX, +18), and characteristic autopsy findings were identified. We report a case of prenatally diagnosed trisomy 18 with a review of literatures.