Background: Availability of smartphones has opened opportunities for expansion and application of mobile-based educational programs which facilitate mothers' education regarding chemical injuries as these injuries significantly affect children` health. Aim: This research aimed to assess the impact of smartphone app based preventive program for mothers regarding chemical substance injuries among their children. Research design: The study's aim was achieved by using a quasi-experimental design. Setting: The research was carried out at Pediatric Outpatient Clinic of Benha University, Benha Teaching, and Benha Specialized Pediatric Hospitals. Sample: A purposive sample was used to select 90 mothers. Tools: Two tools were used. I: A structured interview questionnaire that included characteristics of the studied sample, knowledge and self-reported practices regarding chemical substance injuries and prevention. II: Scale to measure attitude of mothers regarding prevention of chemical substance injuries and smartphone app-based preventive program. Results: Positive statistically significant correlations were found between mothers' knowledge, reported practices and attitude regarding chemical substances injuries and prevention of complications at pre and post implementation of smart phone app based preventive program. Conclusion: Smartphone app-based preventive program have significantly helped to improve knowledge, enhance practice, and modify attitude of mothers regarding chemical substance injuries among their children. Recommendations: Smartphone app-based preventive program should be provided to mothers to improve their knowledge and practices regarding other home injuries.