In lung transplant recipients, Gastro esophageal reflux is associated with increased incidence of acute rejection and earlier onset of chronic rejection. We report a case of single lung transplant that had severe vascular rejection due to the reflux of esophageal contents. Patient is a 41 year old gentleman who had left sided single lung transplantation for end stage pulmonary fibrosis with unknown origin. After 6 months of transplant FEV1 started coming down. TBLB showed rejection grade 2-3. Before giving him the methylprednisolone because of dilated esophagus in CTscan and dark secretion in bronchoscopy, barium swallow was performed which showed dilated esophagus that terminated in a beak-like narrowing. Manometry confirmed the achalasia. Antireflux advises was given to the patient. No change was taken to the medications. 3 weeks later FEV1 got back to the previous level (from 40 to 53%). Then esophagus was dilated by balloon and after 11 months of transplant there are no more declines in spirometric values. Even reflux of esophageal contents can induce acute rejection after lung transplantation.