HIV infection leads to progressive deterioration of immunity. Upper gastrointestinal symptoms are often reported in patients with this infection. The aim of the study was to evaluate morphological changes in upper gastrointestinal tract mucosa and prevalence of opportunistic infections and Helicobacter pylori in HIV-infected people in relationship to the degree of immunosupression. We studied 94 HIV-infected patients with dyspeptic symptoms, 47 suffered from severe immunodeficiency expressed by low CD4+ lymphocyte count below 200/ mm3. Control group consisted of 52 non HIV-infected patients. During endoscopy, gastrointestinal tract mucosa was evaluated and biopsy samples were taken from gastric body and antrum for histopathological analysis and rapid urease test. In patients with CD4+ lymphocyte count below 200/mm3, endoscopic examination revealed significantly more frequent esophageal candidiasis (36%); whereas reflux esophagitis (13%) was significantly less often diagnosed in comparison to the rest of the patients. Duodenitis and duodenal erosions were also less frequent in them. Prevalence of Helicobacter pylori infection in gastric antrum was significantly lower in HIV-infected patients with severe immunodeficiency (40%) in comparison to the rest of the patients (72%) and control group (69%). Chronic active gastritis of the antral mucosa was less frequent in HIV-infected patients with CD4+ lymphocyte count below 200/mm3.