Background: Meaning in life has been depicted as an important psychological resource for both children and adults. Objective: The specific aims of this study were to quantify the rates and severity of suicidal ideation in a sample of 6165 Chinese children and adolescent students from a wide range of areas across China and to investigate whether mental health status and meaning in life would be the predictors for suicidal ideation. More importantly, meaning in life was investigated as a possible moderator and a mediator of the influence of mental health status on suicidal ideation. Methods: Descriptive statistical analyses, Pearson correlation analyses, and hierarchical regression analyses were adopted as methods of data analyses. Results: Approximately 33.71% of students reported having suicidal ideation. Both mental health status and meaning in life were strong predictors of suicidal ideation. Results indicated that poorer mental health status was significantly associated with more severe suicidal ideation, whereas a weaker sense of meaning in life was significantly correlated with greater suicidal ideation. Mediation analysis showed that meaning in life partially mediated the link between mental health status and the severity of suicidal ideation. Specifically, students who experienced poorer mental health status might be more likely to report having a weaker sense of meaning in life, which in turn promotes greater suicidal ideation. Moderation analysis showed that the impact of mental health status on suicidal ideation was significantly greater among children and adolescents with a weaker sense of meaning in life. Conclusions: Results are discussed with regard to the potential value of meaning in life and mental health status in building predictive models of suicidal ideation.