2Background: Helicobacter pylori found in the gastric mucosa of more than 50% of the human popula-tion, and the risk of stomach cancer increases in infected individuals. Materials and Methods: In this retrospective study, the target population was patients admitted to Namazi Hospital in Shiraz during 2009-2018. For this purpose, 3099 records of patients were analyzed with regard to history of endoscopy, age, gender, chief complaint, reason for referral, initial clinical diag-nosis, pathology result, and presence of Helicobacter pylori. Results: Among all the examined individuals, 776 (69. 1%) of women and 1197 (60. 9%) of men were in-fected with Helicobacter pylori. The most and the least affected individuals fell in the age group 59-36 years with 899 (0. 29%) and 19-35 years with 573 (18. 5%), respectively. Of the participants, 1380 (69. 9%) had a history of endoscopy. The most common causes for patient's chief complaint or the reason for go-ing to the hospital or referring for hospitalization were burping (11. 1%), vomiting (9. 8%), hematemesis (9. 8%), heartburn (9. 7%) and dysphagia (9. 6%). In terms of the initial clinical diagnosis, the most causes pertained to chronic gastritis (21. 6%), atrophic gastritis (18. 7%), gastric ulcer (16. 8%) and intractable vomiting (14. 0%). Conclusion: The results of this study showed that the prevalence of Helicobacter pylori has decreased in recent years and that being infected is related to gender and age.