The objective of this study was to clarify the relationship between self-control and addiction on smart phone of adolescents. 300 copies of survey were distributed to students in middle/high schools located at the jurisdiction in Seosan-si, Chungnam. Among them, 19 copies with incomplete or poor responses and also cases for not using smart phone were excluded. Total 281 copies of survey were used for the analysis. In order to identify correlation among major variables, Pearson correlation analysis was conducted. In addition, multiple regression analysis was conducted to verify the effect of self-control on addiction of smart phone. Results in this study are summarized as follows. First of all, there was a significant difference on the addiction of smart phone depending on the gender. Female students turned out to use smart phone and also SNS longer than male students. Male students turned out to spend more time in studying and game than female students. In addition, there was a statistically significant difference in terms of using period, purpose of usage, and using hours of smart phone among the group of addicted subjects among middle and high school students. Secondly, according to the result of analysis on the relationship between self-control and addiction on smart phone, self-control turned out to be related with addiction on smart phone. A group of subjects with high risk of using smart phone turned out to be higher in sub-factors of self-control (impulsivity, preference of simple assignment, pursuance of adventure, preference of physical activities, self-centered attitude, and temper) than the group of regular users and the group of users with potential risk. Third, there was a positive correlation among sub-factors of self-control and addiction on smart phone. Among sub-factors of self-control, there was a high correlation in an order of impulsivity, preference of simple assignments, self-centered attitude, and temper. However, there was no significant correlation between addiction on smart phone and pursuance of adventure/preference of physical activities. This study has confirmed that there was correlation between self-control and addiction on smart phone of adolescents. In addition, this study is meaningful in that it has clearly verified the correlation among sub-factors of self-control.