This study was performed to determine the smartphone addiction and it's association with various related factors such as sociodemographic characteristics, family life characteristics, school life characteristics, health related characteristics, psychosocial factors(self esteem, anxiety, locus of control) among the middle school students in rural areas. The self-administered questionnaire were given to 630 middle school students during the period from May 1st to 31th, 2014. As a result, the distribution of smartphone addiction group among all subjects was 24.1%, and smartphone addiction is so complicatedly influenced by various factors as well as sociodemographic characteristics, school life characteristics and health related characteristics, to a greater extent, by self esteem, anxiety and locus of control. Therefore the effective strategy for decrease of smartphone addiction among the middle school students requires the efforts to improve their psychosocial factors.