Background: Suicide is a major cause of death among adolescents, with suicidal ideation (SI) being a common symptom in this group. SI arises from a complex mix of biological, environmental, and psychological factors, however, the specific relationships between them is not yet fully understood. Network theory has been proposed as a promising framework to analyze these relationships, with latent network models (LNM) offering a novel approach to capture their complex underlying dynamics. Methods: We examined a SI-based LNM in a sample of 1539 students from secondary public schools (M = 15.336; SD = 1.022; female = 52.39 %). The model included depressive and anxiety symptoms, feelings of hopelessness, emotion regulation strategies, and cognitive-behavioral and problem-solving skills. Strength and expected influence indices were calculated for each variable. Results: Hopelessness and depressive symptoms showed the highest strength and expected influence values within the model, respectively. Our findings suggest that hopelessness might play a crucial mediating role linking common mental disorders and emotion regulation strategies with SI in adolescents. Expressive suppression had a direct and negative association with SI, showing its underlying regulatory role when other factors are controlled. Cognitive-behavioral and problem-solving skills showed weak links with SI. Conclusions: Primary care- and school-based interventions should center on hopelessness as a relevant direct predictor for SI, and potential mediator in the course of SI. A combination of research and intervention efforts directed at reducing hopelessness in youths may prove to be essential for reducing suicide-related behaviors altogether.