Background: Early marriage is a public health problem that violates the adolescent girl's basic human rights. The Sustainable Development Goals had incorporated early marriage in target 5.3, aiming to eliminate by 2030. Aim of the study was to evaluate the effect of empowerment program on knowledge, attitude and practice of rural adolescent girls regarding health consequences of early marriage. Subjects & Methods: Design: A quasi-experimental research design was utilized. Setting: The study was conducted in two preparatory schools at Zagazig city. Subjects: A sample of 100 female students randomly selected from east and west educational administrations. Tools of data collection: A self-administered questionnaire consists of four parts; socio demographic characteristics, knowledge regarding health consequences of early marriage, attitude toward early marriage and healthy practices of adolescent girls. Results: The study results revealed that there were statistically significant improvements in knowledge, attitude and practice of adolescent girls regarding health consequences of early marriage after the program (p < .0001). The result also showed that knowledge score was positively correlated to attitude score (r = .379) and practices score (r = .399) at post program phase. Conclusion: The program's implementation was shown to be successful in improving adolescent girls' knowledge, attitude and practices regarding health consequences of early marriage. Recommendations: Further researches should continue to identify determinants of early marriage to assist in building more girl-centered interventions and norms change interventions that empower adolescent girls, particularly, in rural areas in order to advocate for themselves against child marriage.