A 4-month-old, intact male, Tosa with a history of a regurgitation, vomiting, and weight loss for three weeks was presented to Animal Medical Center, Chonbuk National University. In Serial plain radiographs, a severely distended stomach was seen and ultrasonogram revealed a nonfunctional pylorus with normal layer comparable with an obstruction of pyloric region by pyloric achalasia. An esophagram and endoscopy revealed normal peristalsis with failure of the lower esophageal sphincter to open, supporting the diagnosis of esophageal achalasia. Megaesophagus was observed on reradiograph and esophagram 11 days later. The clinical signs and esophageal dilation were resolved without resorting to any treatment.