Background: Nurses in the critical care setting know that the causes of medication errors are both varied and complex. Medication errors have serious direct and indirect results and consequences on patient outcomes and the healthcare system overall. Nurses are considered key players in the medication administration process and may cause or report different forms of medication errors. The perception of nurses about medication errors has not been well-investigated to date in Jordan. Objectives: This study sought to describe nurses’ perceptions about medication errors in Jordanian hospitals, including what constitutes a medication error, causes of medication errors, what is reportable, the percentage of reporting, and what barriers to reporting exist. Methods: This descriptive cross-sectional study employed a self-report survey method to assess the perception of 300 critical care registered nurses from three governmental hospitals in Jordan who were selected using a cluster random sampling method. Results: Study findings revealed that the nurses surveyed had different perceptions about the causes and reporting of medication errors. Most of the nurses reported incidence of medication errors during their clinical practice. The estimated average of medication errors reported to the nurse manager using incident reports was about 61%. Using six clinical scenarios reflecting medication errors to assess the perception, 77% of nurses perceived the clinical scenarios to be medication errors, 68% of nurses believed that the events should be shared with the physician, and 57% believed that formal incident reports should be written for those events. The most prevalently perceived cause of medication errors was a failure of the nurse to check the patient's identification band when administering medications. The majority of participants suggested that nurses are usually sure when medication errors should be reported; however, the failure of them to report a medication error was largely because they did not think the error was serious enough to warrant reporting. Conclusions: Reporting medication errors should be recognized as opportunities for improvement rather than means for penalty. Medication errors indicate a defect in the healthcare system of the hospital, not individuals. Open channels of communication should be established between nurses and their managers in order to enhance medication error reporting. Moreover, special educational courses in medication handling should be included in the nursing undergraduate education and hospital orientation programs.