Background: Mobile applications developed to promote online safety for adolescent children are underutilized and rely heavily on parental control features that monitor and restrict their child's mobile activities. Parents should use mobile apps that allow to monitor and restrict their children's activities online. Aim: This study aimed to assess parents' perception of protective method regarding the risks of mobile applications used by their adolescent children. Research design: A descriptive design was used in this study. Sample: A purposive sample included 375 parents who have child in age between 10 to 19 (Adolescent), have a smart phone and use internet. Setting: Home visit in Elbawity at Bahariya Oasis -Egypt. Tool of data collection: One tool included four parts, 1st part: Socio-demographic characteristic, 2nd part: Prevalence rate of mobile phone use, 3rd part: Parents' knowledge about risks of mobile application uses and protective methods, 4th part: Parent's reported practice about protective methods used. Results: 55% of the studied parents had poor knowledge. While 15% of them had good knowledge. 60% of studied parents had unsatisfactory reported practice and 40% of the studied parents had satisfactory reported practice. Conclusion: More than half of the studied parents had poor total knowledge, also less two third of them had unsatisfactory total reported practices regarding mobile risks. There is statistically significant relation between parents' sociodemographic data, their knowledge, and reported practices. Recommendations: Provide health education program for parents and design booklets about risks of mobile application uses and protective methods.