A novel histologic phenotype of chronic esophagitis, ie, lymphocytic esophagitis, is reported in 20 patients. Lymphocytic esophagitis is characterized by high numbers of intraepithelial lymphocytes (IELs) gathered mainly around peripapillary fields and by none (n = 12) to occasional (n = 8) CD15+ intraepithelial granulocytes. IELs expressed CD3, CD4 (42%), CD8 (36%), and granzyme B (0.2%), whereas T-cell intracytoplasmic antigen (TIA) 1 was not expressed. Of the 20 patients, 11 (55%) were 17 years or younger. Of 20 patients, 5 had no symptoms in the upper gastrointestinal tract. Only 4 (20%) of 20 patients had symptoms of gastroesophageal reflux disease and 6 (30%) of gastroduodenitis; 2 (10%) had celiac disease; 4 (20%) had carcinoma of the esophagus (1) or elsewhere (3); 1 (5%) each had hiatus hernia, gastric ulcer/asthma/blood hypertension, Hashimoto thyroiditis, and cirrhosis/diabetes; and 8 (40%) had Crohn disease. Hence, a novel histologic phenotype of chronic esophagitis called lymphocytic esophagitis is reported. Because phenotype is defined as the visible features resulting from the interaction between the genetic makeup and the environment, it is suggested that those factors might have a decisive role in the development of lymphocytic esophagitis.