H. pylori infection is mainly spread in the kind of gastroduodenal diseases: chronic gastritis, peptic ulcer disease, MALT-lymphoma, gastric cancer. According to certain literature, the mentioned bacterium causes diseases of other visceral organs of humans. Study of the aggravating impact of this infection is under the attention of the scientists. However, other infectious agents, including fungi, other bacteria, parasites, and viruses and their role in different gastroduodenal diseases are not studied enough. The aim of our study was to identify mucous (parietal) gastroduodenal microflora in patients with different diseases of this zone. 390 patients with chronic gastritis (CG), peptic ulcer diseases (PUD) and gastric cancer (GC) were included in the study. The resection materials and biopsy specimens were taken during the operation or endoscopy procedures. Identification of strains H. pylori, Candida spp and others was performed by established methods, on the basis of morphological, tinctorial, cultural and biochemical properties. Microflora of patients with different gastroduodenal diseases is diverse enough. It is represented by facultative, obligate anaerobes, microaeropilic bacteria. More frequently, there were H. pylori and Candida sp, as well as in associations and monocultures. The obtained results confirmed the wide distribution of H. pylori and Candida spp and their frequent coexistence in patients with gastric cancer, chronic gastritis and peptic ulcer disease. Microflora of patients with CG and GC was represented on 11 species. Microflora of patients with PUD-13 species was more diverse.