Congenital esophageal stenosis (CES) is a rare condition that is associated with various foregut symptoms. The aim of the current study was to investigate esophageal motor function in pediatric patients with isolated CES.Four boys with CES (age, 3 weeks to 4 years old) were studied before treatment. The initial symptoms were dysphagia or stridor. The CES was caused by fibromuscular stenosis (FMS) in 2, tracheobronchial remnants (TBR) in 1, and membranous diaphragm (MD) in 1. An esophagram, endoscopy, 24-hour esophageal pH monitoring, and manometry were conducted.The esophagram showed the stasis of contrast medium proximally to the distal esophageal narrowing in FMS/TBR patients. Endoscopic esophagitis was not found in any patients. Three patients were documented with pathologic esophageal acid exposure by 24-hour esophageal pH monitoring. Manometry showed that esophageal contractions predominantly were synchronous in FMS/TBR patients but were peristaltic in an MD patient. Basal lower esophageal sphincter (LES) pressure was at least 20 mm Hg in all. Swallow-induced LES relaxations were incomplete in FMS/TBR patients.The presence of gastroesophageal reflux and impaired esophageal motility are common in patients with CES.