Chronic erosive gastritis has been regarded as an unusual, ill-defined condition of unknown etiology. We report a retrospective study of 40 patients in whom this diagnosis was made relating radiologic findings to patients' age, symptomatology and possible etiologic factors. The condition is more common than previously suspected and requires careful technique combining double contrast and graded compression to demonstrate fine mucosal abnormalities. The radiologic appearance is of mucosal mounds measuring 3-11 mm in diameter with central barium collections and numbering from 3-27 per examination. Antral involvement occurred in 90% of patients, with diffuse involvement of both antrum and body in 58%. Several linear erosions measuring up to 15 mm in length were also demonstrated. Chronic erosive gastritis is most severe and symptomatic between 40 and 60 years, becoming sub-clinical in the elderly. Symptoms mimic those of a peptic ulcer or gastric neoplasm and are more severe the more extensive the disease. Gastric irritants, virus infection and Crohn's disease were possible etiologic factors in some patients in this study.