Background: Anemia is a serious public healt h problem affect ing a third of worldâ€™s rnpopulation. It is associated with increased morbidity and mortality in older adults and alsornrelated to lowered work capacity, reduced ability to execute daily activities, decreasedrncognitive function and fatigue. There are different causes for the development of anemia. rnObjective: The objective of this study was Assessment of Helicobacter pylori infectionrninduced iron deficiency anemia and associated factors for the infection among dyspeptic adultrnpatients visiting Shashemene Comprehensive Specialized Hospital, Ethiopia. rnMethods: Institution based cross-sectional quantitative study was conducted in ShashemenernComprehensive Specialized Hospital from January 2020â€“ November 2020. Data was collectedrnfrom dyspeptic adult patients visiting medical OPD. A total of 328 dyspeptic adult patientsrnwere selected by using systematic random sampling technique. Data were coded, entered andrnanalyzed by SPSS version 23. Chi-square test, logistic regression and independent t-test werernused in the analysis and a P-value of less than 0.05 was considered statistically significant. rnResults: Of a total 328 study participants, 38(11.6%) stool antigen tests of H. pylori werernpositive. The prevalence of anemia among HP infected was higher (50%) than uninfectedrn(19.3%) patients (Ï‡2=17.941, P value=0.000). The mean and SD values of Hgb, Hct and RBCrncount were significantly different between H. pylori infected and uninfected patients. H. pylorirninfection was significantly associated with source of drinking water (AOR=5.136, 95% CIrn(1.217, 21.685), p=0.026). On the other way there was no significant association among age,rnsex, family size, educational level, marital status, hand wash after toilet use, hand washingrnbefore meal, body mass index, income, parasitic infection, residence, alcohol drink, tobaccornuse and chat chew with H. pylori infection. rnConclusion and Recommendations: There was an association between H. pylori infectionrnand iron deficiency anemia. Individualsâ€™ sources of drinking water from river and well waterrnwere identified as major risk factor for H.pylori infection. So, it is recommended thatrneducating patients to treat drinking water before use by different techniques.