The purpose of this study was to examine the influence of academic stress on smartphone over-dependence and the moderating effect of parent-adolescent communication on the relationship between academic stress and smartphone over-dependence among middle school students. For this study, 402 students, the participants in this research were 2 grade students at middle school. And analysis using SPSS 21.0 was performed. The main results are summarized as follows. First, academic stresses perceived by adolescents showed a positive correlation with smartphone over-dependence, and parent-adolescent communication showed negative correlation with smartphone over-dependence. Second, parent-adolescent communication moderated the relationship between academic stress and smartphone over-dependence. In this study, the positive communication between parents and their adolescent moderates the relationship between academic stress and their smartphone over-dependence, which means that the quality of parent-adolescent communication can serve as a protective factor to prevent smartphone over-dependence. Since the number of participants in this study is limited to U city, it is necessary to secure sufficient representativeness through large-scale sampling across the country.