Background: Sexual harassment is a widespread and serious social problem in Egypt. It is affecting all parts and all members of the Egyptian society, often on a daily basis. The aim of this study was to evaluate the effect of preventive program for secondary school female students to protect themselves from sexual harassment. Research design: A quasi-experimental design was used. Setting: This study was carried out at governmental secondary schools in El Sharabia District at North Cairo governorate. Sampling: Multistage random sample technique was used in this study, 235 students were recruited from a total number of students in eight classes. Tools: A self-administrated questionnaire for the secondary school female students included; socio-demographic characteristics, factors leading to sexual harassment, secondary school female students' knowledge regarding sexual harassment, and assertive behaviors and self defense methods regarding sexual harassment protection. Results: After preventive program implementation the main study results revealed that post preventive program, knowledge level of the secondary school female students, also self defense methods and assertive behaviors regarding protecting themselves from sexual harassment improved. Conclusion: Overall, secondary school female students' knowledge increased from pre- to post-test for students participating in the sexual harassment preventive program regarding to sexual harassment. Pretest, the majority of the students had less acceptable level of self defense methods and assertive behaviors about sexual harassment, while posttest their acceptable level was improved for the majority of them. Recommendation: Training in self-protection and how to avoid being exploited should be available to secondary school female students