BACKGROUND AND OBJECTIVE: Gastroesophageal reflux disease (GERD) is one of the common gastrointestinal tract diseases. Association between H. pylori infection and GERD is a matter of debate and some studies reported inverse relationship. The aim of this study was to investigate the association between H. pylori infection and erosive GERD in patients who referred to teaching hospitals of Babol University of Medical Sciences, Babol, Northern Iran.METHODS: A total of 911 patients with GERD, including 485 men and 426 women, were enrolled in this Cross Sectional study, underwent endoscopy and then two biopsies were taken from gastric body and antrum to evaluate gastritis and H. pylori infection. All patients were assigned in two groups, patients with erosive GERD (Erosive Reflux Disease, EGERD: 574) and patients with nonerosive GERD (Nonerosive Reflux Disease, NERD: 346). Other variables (age, gender, smoking, opium, BMI, hiatal hernia, duodenal ulcer, gastritis, esophagitis and its severity) in these two groups compared.FINDINGS: In this study 911 patients (mean age 45.7±16.2 years) were evaluated. No statistically significant association between gastric H. pylori infection and EGERD was found. Although, there was significant association between age more than 50, male gender, duodenal ulcer, hiatal hernia and severe gastritis with EGERD, however, this association was not found between smoking, opium and BMI with EGERD.CONCLUSION: In this study no association between H. pylori infection and EGERD was found. Further study is required to show the impact of H. pylori eradication in patients with GERD.