The objective of the present study was to identify the factors influencing the smartphone addiction among college students and to obtain basic information in terms of enhancing proper use of the smartphone. Based on the previous literature with constructs of depression, aggression, self-control and smartphone addiction, a research model was prepared. A total of 332 students were selected from 5 universities in G Metropolitan City and collected data were analyzed through hierarchical multiple regression. The major results of the study were as follows. First, self-control was the most powerful predictor of smartphone addiction. Second, anger caused smartphone addiction to increase whereas social experience caused smartphone addiction to decrease. Third, depression did not cause smartphone addiction to increase. Finally, implications for preventing and decreasing the smartphone addiction among college students were also provided.