Background/Aims: The aim of this study was to investigate the relationship among squamocolumnar junctional inflammation (carditis), reflux esophagitis, and Helicobacter pylori (H. pylori) infection. Methods: Gastrofiberscopy was performed for 221 patients with various gastrointestinal symptoms. Endoscopic biopsies were performed at the distal esophagus of 3 cm above squamocolumnar junction (Z-line), Z-line, antrum, and body. Biopsy specimens were assessed for density of neutrophils and mononuclear cells (each scored 0-3), and for the presence of H. pylori. A carditis score above 2 was considered positive. Results: Among the 221 patients, 107 cases were defined as reflux esophagitis (RE) group and remaining 114 cases were defined as control group. The prevalence of carditis was significantly different between the two groups (RE, 35.5%; controls, 54.4%, p=0.005). The prevalence of H. pylori infection was also different significantly between the two groups (RE, 40.2%; controls, 57.9%, p=0.009). The relationship between H. pylori infection and carditis (p=0.001) or intestinal metaplasia (p=0.033) was statistically significant. Conclusions: Carditis and H. pylori infection can not be a marker of reflux esophagitis. H. pylori infection is associated with carditis and intestinal metaplasia at squamocolumnar junction. (Korean J Gastroenterol 2001;38:319-324)