Preterm infant is truly a global problem, is a major determinant of infant mortality and morbidity and has long-term adverse consequences for health. The aim: was to evaluate the effect of mothers’ health education based on health belief model to promote health of preterm infant related to sudden infant death syndrome. Design: A quasi-experimental design was utilized. Sample: convenience mothers and their preterm infants consisted of 70. Setting: The study was conducted in the Neonatal Intensive Care Units at Benha Specialized Pediatric Hospital and University Hospitals. The required data was collected used the following tools, structured interview sheet; baseline characteristics of mothers and infant; knowledge about sudden infant death syndrome sheet , questionnaire developed based on the health belief model and reported safety sleep practice according to American Academy of Pediatrics. Results: The study results revealed that mothers who received the health education demonstrated significant higher mean score of knowledge, health belief model and reported sleep practice toward their preterm infants after 1 month from hospital discharge; these results support the proposed study hypotheses. Conclusion: There was positive effect of health education in improving the mother’s knowledge, sleep practice as well as health belief regarding sudden infant death syndrome. Recommendation: Guidelines for creating hospital policy should be available, including the American Academy of Pediatrics risk-reduction recommendations, which lists step-by-step instructions for implementing a policy within the hospital setting