Background: Preparatory school students who use the internet and electronic devices have access to new socializing opportunities. However, some situations negatively impact their psychosocial health as well as psychological risks such as cyberbullying that leads to feeling of sadness, fear, and even suicidal thoughts. Aim: The study aimed to evaluate the effect of preventive strategies education on knowledge and practices regarding social media cyberbullying among preparatory school students. Design:  One-group quasi-experimental design with pre-post evaluation was employed. Setting: Two educational zones of Sohag Governorate were represented by the four preparatory schools where the study was carried out. Subjects: This study comprised 250 Students enrolled in preparatory schools and recruited through a multi-stage sample technique. Tools of data collection: there were three tools used: Tool I: Structured Interviewing Questionnaire: Tool II: Preparatory school Students' knowledge Questionnaire, Tool III: Preparatory school Students' practices Questionnaire, Tool IV: Cyber-Aggression Scale (CYB-AGS) to assess cyberbullying practices. Results: After the educational intervention, the majority of the studied preparatory school students have enough knowledge and practices about social media cyberbullying prevention techniques. Furthermore, a stronger and statistically significant negative correlation was observed between knowledge and cyberbullying practices after schooling as compared to before education. Between the examined preparatory school students' total knowledge and practice scores for preventive techniques of social media cyberbullying before and after education, a highly statistically significant difference was found at P < 0.001. Conclusion: Preventive Strategies education was effective strategy in improving the knowledge and practices regarding social media cyberbullying among preparatory school students. Recommendation: Creating and implementing more ongoing educational programs to raise preparatory school students' awareness level of cyberbullying prevention techniques