Nowadays smartphone use is increasing drastically. There is a higher prevalence of smartphone addiction in some specific personality traits. The goal of this study is to evaluate the association of smartphone addiction with personality traits. This study is correlational research. Three hundred and eighty two students of Tehran universities were asked to answer the smartphone addiction scale (SAS) questionnaire and the Persian version of the Cloninger temperament and character inventory (TCI) questionnaire. After the smartphone addiction questionnaire assessment, individuals with smartphone addiction were identified and compared to the non-smartphone addicted group in terms of personality traits. One hundred and ten individuals (28.8%) were prone to smartphone addiction. Mean scores of people with smartphone addiction were higher in novelty-seeking, harm avoidance, and self-transcendence than the non-addicts and were statistically significant. In persistence and self-directedness, the mean scores of the smartphone addiction group were lower than the non-addicts and were statistically significant. Individuals with smartphone addiction had higher reward dependence and lower cooperativeness however they were not statistically significant. high novelty seeking, harm avoidance, self-transcendence, low persistence, and self-directedness which indicate narcissistic personality disorder, could have a role in smartphone addiction.