Aim of the study: assessment of the nurses' knowledge and practice regarding medication preparation and administration errors in neonatal units. Research design: An exploratory descriptive research design. Setting: NICU belongs to two hospitals: Minia University for Obstetric & pediatric and Minia general hospital. Subjects: A Purposive sample included all nurses on duty, at the previously mentioned settings (N=60). Research tools: Tool (I): Questionnaire Sheet that included: Part 1: Socio-demographic data of studied nurses such as age, qualification, ..etc. Part 2: nurses' knowledge about medication preparation and administration such as concept of medication, medication preparation, medication administration errors, etc. Tool (II): Observational Checklist Sheet. Results: It was found that around two thirds of the nurses (73.3%) have average knowledge and total practice score around more than half (51.7%) of the nurses have average total score. There was high strong positive statistical significant correlation's was found between the total scores of knowledge and practices of nurses' knowledge and practices (r=0.89). Nurses' who were working at MUHOP had significantly higher mean scores of total knowledge and practice than those who were working at Minia General Hospital, with high statistical significant difference was illustrated (P.0.02). Conclusion: Nurses had average knowledge and practice, toward medication preparation and administration errors in neonatal units and high significant, positive correlation between knowledge and practice of staff nurses towards medication preparation and administration errors. Recommendation Prepare a structured educational program regarding medication preparation and administration errors to improve knowledge and practice for nurse staff.