Background: The outcome of Helicobacter pylori infection has been related to specific virulenceassociated bacterial genotypes. The best known genotypic virulence factors of H. pylori are cytotoxinassociated gene A (cagA) and vacuolating cytotoxin gene A (vacA). The objective of this study was to assess the relationship between H. pylori cagA and vacA status and histopathological findings. Objectives and Methods: The subjects consisted of 270 patients, (128 men and 142 women, mean age was 43 years,). Biopsy specimens were obtained from astric bod and antrum to mononuclear and polymorphonuclear cell infiltration, atrophy and intestinal metaplasia, histologic evidence of Helicobacter pylori infection. HP was iudaed by 5 different methods: culture, histology, immunohistochemistry, rapid urine test and serum IgG antibodies against HP. Pepsinogen and gastrin concentrations were determined by radioimmunoassay. Results: Almost Helicobacter pylori strains in Vietnam had eastern type cagA (91.3 percent). Western type cagA was 3.9 percent and cagA negativity was 4.9 percent. 100 percent of patients had vacA s1. There was significantly difference in rate of HP strains with vacA m1 between Hanoi and Hochiminh City (57.7 percent compared with 34.0 percent, p 0.05). Patients of HP infection was related to the risk of atrophy (OR