Aim: To determine the willingness and barriers of Neonatal Intensive Care Unit (NICU)-based nurses in Malaysian hospitals in reporting medication errors. Background: Reporting incidents is important in improving patients’ safety and developing a healthy culture of learning from mistakes. Method: Three self-developed scenarios, ranging from mild, moderate to severe medication administration errors, were used to identify nurses’ willingness to report an error. A validated questionnaire assessing barriers to reporting errors was adapted. The sample size calculated was 139. All 22 NICUs in government-funded hospitals were approached. Nurses were randomly recruited and given a URL to access the online questionnaire. Results: Of 182 nurses from 15 hospitals who participated, 91.2% (n=166) were willing to report medication errors and patient safety was the main concern to report it. Among the nurses (n=16, 8.8%) who chose not to report medication errors, they were worried about getting into trouble (87.5%), information being shared with managers (56.3%), disciplinary actions and medico-legal issues (50.0%). Conclusion: Most NICU nurses were willing to report a medication error, and the barriers to the minority of them not reporting should be given attention. Implications: Reassurance by the managers for not penalizing the nurses who report an error should be emphasized in the incident reporting policy.