Two theoretical models were constructed to illustrate how stressful events, family and friends support, depression, substance use, and death attitude mutually influence to create cumulative risks for suicide. The models were evaluated using structural equation modeling. Results showed that suicidality was strongly predicted by death attitude, depression, and substance use which together form a dangerous combination of risk factors at the personal level. Within the adolescent's social environment, stressful events increased suicidality through intensifying depression, substance use, and death acceptance, whereas family and friends support lowered it, partly through reducing stress and death acceptance. The effect (direct and indirect combined) of family support was much stronger than that of friends support. Enhancing stress coping ability, promoting positive family relationships, and attacking attitudes supportive of death might be the best strategies to prevent youth suicide.