Introduction: The risk of dose errors is high in paediatric inpatient settings. Computerized provider order entry (CPOE) systems with clinical decision support (CDS) may assist in reducing the risk of dosing errors. Although a frequent type of medication error, the prevalence of dose errors is not well described. Dosing error rates in hospitals with or without CPOE have not been compared. Objective: Our aim was to conduct a systematic review assessing the prevalence and impact of dose errors in paediatric wards with and without CPOE and/or CDS. Methods: We systematically searched five databases to identify studies published between January 2000 and December 2017 that assessed dose error rates by medication chart audit or direct observation. Results: We identified 39 studies, nine of which involved paediatric wards using CPOE with or without CDS. Studies of paediatric wards using paper medication charts reported approximately 8–25% of patients experiencing a dose error, and approximately 2–6% of medication orders and approximately 3–8% of dose administrations contained a dose error, with estimates varying by ward type. The nine studies of paediatric wards using CPOE reported approximately 22% of patients experiencing a dose error, and approximately 1–6% of medication orders and approximately 3–8% of dose administrations contained a dose error. Few studies provided data for individual wards. The severity and prevalence of harm associated with dose errors was rarely assessed and showed inconsistent results. Conclusions: Dose errors occur in approximately 1 in 20 medication orders. Hospitals using CPOE with or without CDS had a lower rate of dose errors compared with those using paper charts. However, few pre/post studies have been conducted and none reported a significant reduction in dose error rates associated with the introduction of CPOE. Future research employing controlled designs is needed to determine the true impact of CPOE on dosing errors among children, and any associated patient harm.