A review of the recent literature on the association between Helicobacter pylori (HP) and stomach carcinoma (SC) is presented. It is established that SC occurs 6-8 times more frequently in persons infected with HP than in non-infected. HP is considered as a co-factor in the development of SC: HP stimulates proliferation of stomach epitheliocytes and is able to produce free radicals having mutagenic properties. Some authors compare the role of HP in the development of SC with that of tobacco in the development of lung cancer. HP possesses procarcinogenic properties which are manifested if contamination occurs during childhood and when combined with genetic and environmental factors.