Background: Medication errors (MEs) are the most common types of medical errors which effecting on pediatric safety. For decrease MEs, we should to have information about difference aspects of MEs. We have no study which assessed the frequency, types and causes of MEs made by pediatric nurses, in Iran.Material and Methods: This was a cross-sectional study, which performed on 53 Pediatric Nurses. Data were collected by a self-structured questionnaire for assessment of MEs contained 3 parts: 1- one question about the fact that, do you had MEs in past 3 months; 2- types of MEs occurred (12 items); 3- causes of MEs from nurses’ perspective (20 items). The MEs in past 3 months gathered through pediatric nurses’ self-report. Descriptive statistics and Chi-square test were used for analysis. Data were analyzed using the SPSS.Results: The majority of participants were female (77.3%), and initial (novice) nurses (33.9%). The results showed that, 31 (58.4%) of nurses were reported at least one MEs history and totally, 131 MEs were occurred in past 3 months. Most prevalent of MEs types were reported: wrong dose (36.6%) and wrong drug preparation (14.5%). Also, most prevalent of MEs causes from Nurses’ perspective were reported: poor medication knowledge (96.2%) and poor calculation skills (73.5%).Conclusion: With using of this study results, we can program for prevention/decrease MEs and enhancing pediatric safety. On the basis of this study, actually we should enhancing level of nurses knowledge by education and to carry out special courses for pediatric nurses.