BACKGROUND: Dyspepsia is frequently encountered in clinical practice globally. It affects 26-45% of Nigerians. Dyspepsia reduces the quality of life and leads to absenteeism. Its association with Helicobacter pylori, a gram negative bacterium has made a major impact on patients’ management. The prevalence of Helicobacter pylori is reportedly high in this environment. In diagnosing the bacterium, attention is shifting more towards non-invasive tests such as stool antigen test. This test has not been well studied among Nigerians. AIMS AND OBJECTIVES: The aim was to determine the prevalence of H. pylori among Nigerian patients with dyspepsia using the stool antigen test. The objectives were 1. To determine the prevalence of H. pylori among Nigerians presenting with dyspepsia and in controls at the University College Hospital, Ibadan, by the stool antigen test. 2. To determine the prevalence of H. pylori among the same population by Ig G serology. 3. To compare the prevalence of H. pylori in patients with dyspepsia with age and sex matched controls. 4. To determine the relevance of H. pylori screening by the stool antigen test in Nigerian patients with dyspepsia. METHODOLOGY: Forty six consecutive patients (20 males, 26 females) and 46 age and sex matched controls were recruited for the study after giving informed consent. All underwent clinical examination. Blood and stool specimens were obtained from all and were tested for H. pylori RESULTS: The mean ages of patients and controls were 40.87 ± 3.31 and 40.83 ± 13.20 years, respectively. Using the stool antigen test, the prevalence of H. pylori among dyspeptics was 67.4% and among controls 78.3%, but this was not statistically significant (p=0.48). Using H. pylori IgG 67.4% prevalence was obtained in the dyspeptics and 91.3% in the controls and was statistically significant. CONCLUSION: The prevalence of H. pylori is high among Nigerians, both in dyspeptics and healthy