Esophageal duplication cysts are rare congenital abnormalities of the foregut and may be associated with other conditions. Association of esophageal duplication with Gastro-Esophageal Reflux Disease (GERD) has not been reported in children. We are reporting a case of a 16 months baby who had antenatal diagnosis of diaphragmatic hernia. Postnatal CTchest, however, suggested a distal esophageal duplication cyst and a contrast esophagogram showed grade-IV GER. A thoracoscopy in another hospital excluded esophageal duplication at that time. Later, he presented with hematemesis in our department and was re-evaluated. Repeat CTconfirmed a persistent 2.5 x 1.3 cm cyst in distal esophagus. Upper GI endoscopy suggested grade-II esophagitis with a wide patent gastro-esophageal junction. The child was treated with left thoracotomy, excision of the duplication cyst and thoracic fundoplication. He had an uneventful post-operative recovery and is doing well at 6 months follow-up.