Sudden infant death syndrome (SIDS) is a prevalent cause of infant mortality under a year, and its reasons remain unclear. However, basic preventive strategies in infant sleeping and sleep surroundings can limit its incidence. Purpose: Evaluating the effectiveness of an educational program on mothers' knowledge and practices for the prevention of SIDS. Design and Method: On 180 recently delivered women, a quasi-experimental study was conducted in the postnatal unit. Data on the mothers and their neonates' characteristics, as well as mothers' knowledge and reported experience with SIDS, were gathered using an interview questionnaire sheet. Results: Before the program, more than 71% of the mothers had little to no understanding of SIDS. Additionally, prior to the educational program, almost half of the mothers showed an unsatisfactory level of practices on SIDS prevention. After applying for the program, the majority of them had adequate knowledge and acceptable practices levels. Conclusion: The training program had a beneficial impact on the mothers' understanding of SIDS and preventative measures. Therefore, enhancing mothers' knowledge and practices on SIDS prevention requires a regular health education program from all health teams during the post-natal period.