Medication error (ME) is the most common preventable cause of adverse drug events which negatively affects patient safety. Inadequate, low-quality studies plus wide estimation variations in ME from developing countries including Iran, decreases the reliability of ME evaluations. To clarify sources, underreporting reasons and preventive measures of MEs, we reviewed Iran current available literature. We searched Scopus, WOS, PubMed, CINAHL, EBSCOHOST and Persian databases (IranMedex, and SID) up to October 2012. Two authors independently selected and one reviewed and extracted data. Results reported by more than 30% of studies considered as the most important topics. Finally 25 articles were included. All study designs were cross-sectional (except for two interventional studies) and in hospital settings. Nursing staff and students were the most observed populations. Individual factor, with “inadequate knowledge of medication” as its most frequent reason, were the mostly reported source of MEs. Fear and reporting process were two most important reporting barriers. The sense of being reprimanded and ignoring to report respectively were their most frequent factors. Anti-infectives were the most frequent drugs involved in MEs. Preventive measures were varied and reporting of their effectiveness was inconsistent. There are still many research gaps which need to be explored by further studies. Based on our findings, further researches may be focused on design, implementation, and evaluation of a ME reporting system as groundwork, assessing systems-related factors to ME alongside individual factors and evaluating the effectiveness of preventive measures for MEs in trials.