Problematic mobile phone use of adolescence has already become an unavoidable social issue on account of the development of communication technology. Since it has a quantity of harmful physical and mental effect, more and more researchers focus on problematic mobile phone use and its influencing factor. According to current researches, personality and self-control has shown to be important predictive variables of problematic mobile phone use. Health belief model（HBM） and its expanded theory shows that personality can impact the change of behavior as a behavioral clues. Dual-systems theory can be used to explain the relationship between self-control and problematic mobile phone use that the former regards as reflection system while the latter as reflecting system. Also researches verified that if one has the traits of conscientiousness, then he or she can be deemed to be highly self-control. What’s more, time monitoring, which is closely correlated with conscientiousness according to some studies, may influence the ability of self-control as cognitive monitoring. We call this theory the self-control model. Therefore, the major problem we focused on was how and to what extent time monitoring and self-control can influence the process from conscientiousness on problematic mobile phone use. This research collected self-reported data from 1200 teenagers in one high school and one middle school in Beijing, which included the grade of junior one and two together with senior one and two. We measured the level of conscientiousness by the Chinese version of the Ten Items Personality Inventory（TIPI-C）. The short version of Mobile Phone Problematic Use Scale（MPPUS）was used to gather the current situation about mobile phone use. Time monitoring was assessed by Adolescence Time Management Disposition Scale（ATMD）. Adolescence Effortful Control Scale from Early Adolescent Temperament Questionnaire-Revised was used to assessed the level of Self-control. The results showed that: (1) Conscientiousness can be used to predict the use of mobile phone through the chain mediator effect of time monitoring and self-control. (2) Conscientiousness can also influence the production of problematic mobile phone use through self-control directly, but the path of this influence is insignificant compared with the former. What comes to the conclusion is as the level of conscientiousness increasing, the stronger perception of time monitoring and higher ability of self-control can lead to a certain reduction of problematic mobile phone use. These findings make contributions to the mechanism about how conscientiousness can impact the problematic mobile phone use, as well as some ideas about how to deal with problematic mobile phone use through behavior modification. Since conscientiousness is relatively stable and difficult to change, improve the level of time monitoring and self-control in order to decrease the behavior of mobile use seems to be quite feasible. But extra behavior modification experiments should be done to prove this method. What’s more, this research focused on the overall use of mobile instead of specific use such as entertainment, study, communication or other, maybe further studies can be done basing on these.