Abstract Conflicts are an inevitable feature of human interactions. Especially in adolescence, conflicts with parents about everyday issues are common mainly due to the change of the parent-adolescent relationship and adolescents' struggle for independence. Aim of the study was to investigate the frequency and intensity of conflict between adolescents and their parents in Assiut Governorate. Research Design: Descriptive correlational research design was used. Setting: The study was carried out at 8 preparatory schools in Assiut governorate. Subjects: One thousand and two hundred adolescents in the selected preparatory schools. The sample was selected by using stratified random sampling. Tools of data collection: Two tools were used, socio-demographic questionnaire and parent-adolescent issues checklist. Results: It was found that 93.9% of adolescents had conflict. Also, 95.4% of preparatory school children in the early adolescents had more conflict frequency than those in the middle adolescents (89.2%). Statistically significant differences were found between the mean score of conflict domains as home tasks, acceptable behavior, family rules/obligations and school concerns domains in the early and middle adolescents. Conclusion: Children in the early adolescents had more conflict frequency than those in the middle adolescents. Recommendation: Health education program for parents to increase their awareness about developmental changes during adolescence period.