Background: Parenteral nutrition (PN) is a lifesaving intervention that is used when enteral feeding is not possible or insufficient for neonate in neonatal intensive care units' neonatal nurses play a critical role in the care of neonates receiving parenteral nutrition in the NICU. Aim of the study was to assess nurses' performance regarding parenteral nutrition at neonatal intensive care units. Research design: Descriptive research design was used to conduct the current study. Setting: This study was conducted in Neonatal Intensive Care Units (NICUs) at Benha University hospital. Subject: purposive sample composed of all neonatal nurses (70 nurses) who are working at the previous mentioned settings at the time of the study. Tools: Data was collected by using two tools Tool (I):-Structured questionnaire interviewing which was consists of three parts. Part (1) personal characteristics of the nurses. Part (2) Neonatal characteristics. Part (3) Neonatal nurses' knowledge regarding total parenteral nutrition. Tool (II): Observation Checklists: The checklists used to assess nurses' practices regarding TPN. Results There were more than half (51.4%) of studied nurses were satisfactory knowledge, more than two thirds of them (70%) had a competent total practice. Conclusion: There was a statistically significant positive correlation between the studied nurses' total knowledge and their total practices. Recommendations: Educational programs for nurses should be conducted to raise their awareness about parenteral nutrition at neonatal intensive care units.