AIM:To determine the risk factors associated with H. pylori infection and possible correlation with clinicopathological parameters.MATERIAL AND METHODS:Gastroduodenal biopsies were examined by rapid urease test and Gram staining. Cag A cytotoxin was detected by in situ hybridization.RESULTS:Risk of H. pylori acquisition reported as following: Males have 1.38 fold, rural residents have 0.63 fold, Nonsmokers have 0.39 fold, mild smokers have 18 fold, and moderate smokers have 1.4 fold while heavy smokers have 1 fold. A person who’s in contact with animals has 1.52 fold risks. Illiterates and patients with primary education have 5.36 & 3 fold risk respectively. Patients under proton pump inhibitor (PPI) therapy have 1.02 fold. Patients under NSAID therapy have 3.48 fold while nonalcoholic Patients have 0.75 fold. Patients using tap water have 0.45 fold risk. H. pylori infection positively correlated with age, weight loss, and heartburn. H. pylori inversely correlated with endoscopic diagnosis, Cag A positivity, and education level. Cag A positivity correlated with animal contact and NSAID usage.CONCLUSIONS:Several life style factors, education, animal contact, using of PPI, and NSAIDs increase the risk of H. pylori infection. Weight loss and heartburn cardinal signs for H. pylori infection. Endoscopic diagnosis and clinicopathological parameters not strictly associated with Cag A positivity.