Background: Health awareness about tobacco use could become one of the most effective strategies available to reduce tobacco use. Aim of study: the study aimed to assess health awareness of teenage school students about risk of smoking on health in slums. Design: A descriptive research design was used to achieve the aim of the current study. Setting: The study was conducted at the preparatory (namely: Nahdet Masr which serve 952 students) and the secondary (namely: El-Zaher which serve 468 students) schools for male at Sharabya districts affiliated to North Cairo governorate. Subjects: Convenient sample (315 students) was used for this study; include multi stage random sample technique was used. Tools of data collection: A self-administered questionnaire format that includes five parts:-Part (1): Socio demographic characteristics of teenage students, Part (2): History of smoking among teenage students, Part (3): Awareness of teenage students about smoking, Part (4): assessment of teenage reported practices, and Part (5):The Four Dimensions of Smoking Attitudes Scale. Results: There was a highly statistically significant relation between students' awareness level and their parents demographic characteristics and Less than two thirds of the studied sample had negative attitude toward smoking cessation compared to more than one third had a positive attitude. Conclusion and recommendations: More than half of the studied students had poor awareness regarding smoking, more than two thirds had incompetent level regarding smoking cessation. Enhance behaviors and information of teenage school students about risk of smoking, Promote teachers with suitable training about how deal ideal with teenage school students that risk of smoking, develop and enforce a school policy on tobacco use.