<p>Problematic mobile phone use has risen steadily in recent years, raising concerns about students’ mental health and prompting growing scholarly interest in its protective and risk factors. However, certain research gaps have been identified. This study adopted a three-wave design to examine how self-control, perceived parental psychological control, and depression jointly influence the problematic mobile phone use among primary school students. A total of 489 fourth- and fifth-grade children (<i>M</i>_age = 10.560, <i>SD</i> = 0.826) completed questionnaires at three time points during one year. Results showed that a higher level of self-control was associated with a lower level of depression and problematic mobile phone use, whereas a higher level of perceived parental psychological control was associated with a higher level of depression and problematic mobile phone use. Furthermore, depression serves as a mediator both between students’ self-control and problematic mobile phone use and between perceived parental psychological control and problematic mobile phone use. These findings indicate that self-control functions as a protective factor, while perceived parental psychological control acts as a risk factor for primary school students’ depression and problematic mobile phone use.</p>