Abstract: Sudden infant death syndrome (SIDS) is a common cause of infant mortality below one year, and its causes remain unknown. However, simple protective practices in infant sleep and sleep environment can dramatically reduce its incidence. Aim: Evaluating the effectiveness of educational program on mothers’ knowledge and practices for the prevention of SIDS. Materials and Method: A quasi-experimental research was conducted in postnatal department at the general hospital in Kafrelsheikh city, Egypt, on 180 newly delivered mothers, free from eclampsia, chronic diseases and a delivered baby did not have health problem as neonatal jaundice or respiratory distress syndrome. Interview questionnaire sheet was used to collect data about characteristics of mothers and their infant; mothers’ knowledge and reported practices about SIDS. Results: More than three-quarters of the mothers did not hear about SIDS and had poor knowledge level about SIDS before the program. In addition, about half of the mothers demonstrated unsatisfactory practice level about SIDS prevention before the program. While the majority of them had good knowledge and satisfactory practices level after program application. Conclusion: There was positive effect of the educational program in improving the mothers’ knowledge, preventive practices about SIDS. Conclusions: A regular health education program is essential for improving the newly delivered mothers’ knowledge and practices regarding SIDS prevention and safe sleep recommendations should be done by the medical staff in the neonatal care unit and on every health visit for the infant in his first year.