en General پژوهشي Research Article Background: Patients, who receive hemodialysis and patients with beta-thalassemia major are at great risk for blood-borne viral infections, chiefly different types of hepatitis. Objectives: This study aimed at assessing the prevalence of hepatitis B and D among hemodialysis patients and patients with beta-thalassemia major in Kashan, Iran. Methods: This cross-sectional study was conducted in 2016 on 108 patients on hemodialysis and 34 patients with beta-thalassemia major in Kashan, Iran. After explaining the aim of the study to the participants and securing their informed consents, data on their demographic and health-related characteristics were collected through a questionnaire. Then, a five-milliliter venous blood sample was obtained from each participant and tested using enzyme-linked immunosorbent assay technique for hepatitis B surface antigen and hepatitis D virus antibody. The data were entered in the SPSS program (v. 16.0) and analyzed using the Chi-square and the independent-sample t tests. Results: The prevalence of hepatitis B surface antigen positivity among patients on hemodialysis and patients with beta-thalassemia major was 3.7% and 8.8%, respectively. Moreover, the prevalence of hepatitis D virus antibody positivity among these patients was 2.9% and 1.9%, respectively. The prevalence of hepatitis B surface antigen positivity among patients on hemodialysis had a significant relationship with history of addiction and history of unprotected sex. Conclusions: The prevalence of hepatitis B and D was respectively 3.7% and 8.8% among hemodialysis patients and 2.9% and 1.9% among patients with beta-thalassemia major. Effective strategies should be employed to minimize the risks of hepatitis B and D transmission among hemodialysis patients and patients with beta-thalassemia major. Moreover, regular screening programs are needed for early diagnosis and treatment of viral hepatitis among these patients. Hepatitis B Surface Antigen,Hepatitis D Virus Antibody,Hemodialysis,Beta-Thalassemia Major 0 0 http://mcj.bums.ac.ir/browse.php?a_code=A-10-1-93&slc_lang=en&sid=1 Mansooreh Momen-Heravi 10031947532846003384 10031947532846003384 Yes Infectious Research Center, Kashan University of Medical Sciences, Kashan, Iran. Tel: +98-09134358226, Email: momenheravi1967@gmail.com Hasan Afzali 10031947532846003385 10031947532846003385 No Infectious Diseases, Kashan University of Medical Sciences, Kashan, Iran