Johanson-Blizzard syndrome is a rare autosomal recessive disorder characterized by aplasia of alae nasi, pancreatic insufficiency, aplasia cutis, anorectal anomalies and postnatal growth restriction. In this case report, we describe the prenatal sonographic findings of Johanson-Blizzard syndrome in a 21-week pregnancy of a consanguineous couple. Sonographic findings of aplastic alae nasi (beak-like nose) and dilated sigmoid colon led to the prenatal diagnosis. This is the first report of the prenatal sonographic diagnosis of Johanson-Blizzard syndrome.