Introduction: Helicobacter pylori infection is a real health problem worldwide. It is the most common chronic bacterial infection in the world, and is particularly prevalent in developing countries. Objective: To determine the frequency of Helicobacter pylori infection and to study the epidemiological, clinical and endoscopic characteristics associated with this infection in Brazzaville. Patients and Methods: This was a descriptive cross-sectional study conducted from January to November 2020, i.e. 11 months. This work focused on 100 symptomatic patients over 18 years old referred for upper GI endoscopy. Gastric biopsies for biological study by urease test and molecular study by real time PCR technique were taken. Results: With a mean age of 46.32 ± 15.20 years, the frequency of Hp infection was 91%, with a female predominance of 53%. The sex ratio was 0.92. The average age was 46.32 ± 15.20 years. Carriage of the infection was more important in households with more than 3 persons, in patients consuming public tap water and in those using both types of sanitary facilities. Endoscopy was indicated for epigastralgia in 93.1% of cases. About 56.14% of the infected patients had normal mucosa versus 12.28% with ulcerated lesions and 22.81% with gastritis. Conclusion: The prevalence of Helicobacter pylori infection is significant in Congo, justifying early detection in order to improve management.