Objective: As a necessity of modern life, the duration of smartphone usage is getting longer. The aim of this study was to investigate the relationship between the levels of smart phone use and physical activity and exercise capacities among university students aged 18-25. Methods: Ninety-three volunteer persons (female=50, male=43) who ages between 18 and 25 years participated in the study. Having collected participants' demographics information, smartphone addiction level was assessed by the Smartphone Addiction Scale-Short Version, physical activity level was assessed by International Physical Activity Questionnaire-Short Form and exercise capacities were assessed by 6 Minute Walk Test. Results: It was found that 52.69% of the participants defined themselves as addicted to smartphone use. There was no significant difference in the level of smartphone addiction between male and female individuals. There was no significant difference between participants' daily use of smartphones and physical capacity. However, 67.8% of smartphone users decreased their physical activity levels independently of duration. Conclusion: Our study finds that smartphone usage does not affect the physical capacity of the young age group however, it seems that it may lead to physical inactivity as a psychosocial problem.