en Epidemiology Epidemiology Review Article Review Article <strong>&nbsp;&nbsp;</strong><strong>&nbsp; Background: </strong>The need for informed policymaking highlights the importance of data on human immunodeficiency virus (HIV) prevalence on key populations. In this systematic review and meta-analysis, we aimed to provide an overview of HIV prevalence in men who have sex with men (MSM) in Iran.<br> &nbsp;&nbsp; <strong>Methods:</strong> We searched literature published between January 2008 and December 2019 to identify studies reporting the prevalence of HIV infection or acquired immunodeficiency syndrome (AIDS) in a population of adult Iranian men with history of sexual contact with other men. We employed Metaprop command in Stata to pool proportions from different studies.<br> &nbsp;&nbsp; <strong>Results:</strong> Among the 16 studies retrieved, 2 were performed on MSM population directly, 7 among people who inject drugs, 4 among prisoners, 2 among the homeless, and 1 among methamphetamine users. HIV prevalence was 7% (95% CI, 5%-10%) based on the meta-analysis, although noticeable heterogeneity existed because of target population, study year, and study location, which imposed limitations to provide a robust summary measure for the prevalence of HIV.<br> &nbsp;&nbsp; <strong>Conclusion: </strong>There is a potential risk of observing a high prevalence of HIV in MSM that could hamper the results of various preventive strategies and their achievements in other subpopulations.<br> &nbsp; Human Immunodeficiency Virus, Acquired Immunodeficiency Syndrome, Sexual and Gender Minorities, Key Population 919 926 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-34-3&slc_lang=en&sid=1 Leila Ghalichi Ghalichi.L@iums.ac.ir 200319475328460065294 200319475328460065294 No Mental Health Research Center, Psychosocial Health Research Institute, Iran University of Medical Science, Tehran, Iran Morteza Naserbakht Naserbakht.m@iums.ac.ir 200319475328460065295 200319475328460065295 No Mental Health Research Center, Psychosocial Health Research Institute, Iran University of Medical Science, Tehran, Iran Mehrdad Eftekhar Ardebili eftekharardebili.m@iums.ac.ir 200319475328460065296 200319475328460065296 Yes Mental Health Research Center, Psychosocial Health Research Institute, Iran University of Medical Science, Tehran, Iran Leila Janani janani.l@iums.ac.ir 200319475328460065297 200319475328460065297 No Preventive Medicine and Public Health Research Center, Psychosocial Health Research Institute, & Department of Biostatistics, School of Public Health, Iran University of Medical Sciences, Tehran, Iran Omid Pournik Pournik.O@iums.ac.ir 200319475328460065298 200319475328460065298 No Preventive Medicine and Public Health Research Center, Psychosocial Health Research Institute, Community and Family Medicine Department, School of Medicine, Iran University of Medical Sciences, Tehran, Iran Fatemeh Tavakoli f.tavakoli@kmu.ac.ir 200319475328460065299 200319475328460065299 No HIV/STI Surveillance Research Center, and WHO Collaborating Center for HIV Surveillance, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran Ali Akbar Haghdoost ahaghdoost@kmu.ac.ir 200319475328460065300 200319475328460065300 No Social Determinants in Health Research Center, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran Hamid Sharifi hsharifi@kmu.ac.ir 200319475328460065301 200319475328460065301 No HIV/STI Surveillance Research Center, and WHO Collaborating Center for HIV Surveillance, Institute for Futures Studies in Health, Kerman University of Medical Sciences, Kerman, Iran