Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 53 8 2015 10 06 454 461 EN Reza Ghotaslou Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. Fatemeh Yeganeh-Sefidan Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran. Behnaz Salahi-Eshlaqi Department of Microbiology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. Hamed Ebrahimzadeh-Leylabadlo Department of Microbiology, School of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran. 2015 10 06 2015 10 06 Acute bacterial meningitis (ABM) is one of the most severe infectious diseases, causing neurologic sequel, and a case fatality rate of 20-30%. The aim of this paper was to summarize the main causes of ABM in Iran. We searched the data for relevant articles using meningitis, etiology, and Iran as search terms. We found 23 papers for inclusion in the review that focused specifically on the ABM, addressing etiology and acute meningitis. Finally, during the 23 years, a total of 18163 cases were recorded, and 1074 cases of which met the criteria for bacterial meningitis. The most common agent associated with bacterial meningitis was S. pneumoniae, followed by H. influenzae, Enterobacter spp., N. meningitidis, and group B streptococcus. The total incidence of ABM during 1991 to 2002 was higher than during 2003-2013. S. pneumoniae still remains a main cause of bacterial meningitis. For improved outcomes, studies are needed to further clarify the etiology of meningitis in Iran, explore simple, accurate, and practical diagnostic tools as PCR, and investigate the most appropriate specific and supportive interventions to manage and prevent meningitis as vaccination. https://acta.tums.ac.ir/index.php/acta/article/view/4265 https://acta.tums.ac.ir/index.php/acta/article/download/4265/4220