Background: University students are at higher risk of smoking. Health-related behaviours related to smoking seem to be important and  affect on  students ‘ academic achievement. Aim: This study aimed to assess  smoking and its associated health behaviors and academic achievement among nursing students in  oct 6 university. Research Design: A descriptive exploratory research design was used to achieve the aim of this study. Setting: This study was conducted at Faculty of nursing in  oct 6 university, Cairo governate, Egypt. Sample: A stratified random sample of 264 nursing students in  oct 6 university was selected. Tool: An online structured questionnaire was used. Results: About one third of the studied nursing students were  smokers  who the majority of them were  male. There was no significant difference between smokers and nonsmokers students regarding the regularity and disturbance of sleep and practicing sport activity (P > 0.05). While, there was a significant difference between them regarding eating fruits or vegetables which were more among nonsmoker (P < 0.05). Conclusion: this study concluded that Less than third of the studied nursing students were smokers who the majority of them were male and low academic achievers may be more vulnerable to smoking but it is not the dominant factor affecting academic achievements. Recommendations: Integrated antismoking programs among students in  universities are recommended to discourage smoking and  raise knowledge of the harmful health impacts of smoking.