Transition of premature infants to direct breastfeeding remains suboptimal in neonatal intensive care units (NICUs) due to lack of formal policies for initiation. Nurses' knowledge and practices have an important role in initiating breastfeeding among premature infants. Aim: The present study aimed to evaluate the effect of educational program on nurses' performance in premature transition from gavage to breastfeeding. Design: A quasi-experimental design was utilized. Setting: This study was conducted at NICU in El Manial Pediatric Hospital affiliated to Cairo University Hospitals. Subject: A purposive sample consisted of 40 nurses from the previously mentioned setting were included. Tools of data collection: Tool I: A structured interviewing questionnaire sheet to assess nurses' personal characteristics and their knowledge regarding initiation of breast-feeding for preterm infants. Tool II: An observational check list tool in order to assess nurses' practice regarding transition of premature infant from gavage to breastfeeding. Tool III: IOWA model for evaluating nurses' beliefs toward transition of premature infant from gavage to breast feeding. Results: There were highly statistical significant differences (P<0.001) concerning nurses' knowledge, practice and beliefs pre/post-implementation of the educational program and there was a positive correlation between total nurses' knowledge, practice and beliefs regarding transition of premature from gavage to breastfeeding post-implementation of the educational program (P<0.001). Conclusion: Implementation of the educational program affect positively on nurses' Performance (knowledge, practice and beliefs) regarding transition of premature from gavage to breastfeeding. Recommendation: Providing nurses in NICUs with continuous educational program regarding transition of premature from gavage to breastfeeding.