Objectives: In this study, we investigated the association between cumulative health risk behaviors (HRBs) and adolescent suicidal behaviors and the moderating effect of future orientation. Methods: We used data were from 4255 adolescents in grades 9th-12th participating in the National Longitudinal Study of Adolescent Health (Wave I-II). We computed a cumulative HRB index by using 14 HRB indicators covering diet, physical activity, sleep, social media use, safety behaviors, and substance use. We used multilevel mixed-effect logistic regressions to analyze associations among cumulative HRBs, future orientation, and suicidal behaviors, adjusting for sociodemographic characteristics, depression, and complex survey design. We included 3-way interaction terms to explore moderation effect. Results: Cumulative HRBs significantly increased the odds of suicidal ideation (AOR = 1.27, 95% CI = [1.17, 1.37], p <. 001) and suicide attempts (AOR=1.26, 95% CI = [1.09, 1.46], p <. 01) across time. Future orientation moderated the associations between cumulative HRBs and suicide attempts differently across race/ethnicity. Engaging more than 4 cumulative HRBs, black adolescents with low future orientation had significantly higher risks of suicide attempts than those with high future orientation. Conclusions: Findings underline cumulative HRBs as significant risk factors for adolescent suicidal behaviors longitudinally. Suicide interventions targeting HRBs could benefit from nurturing future orientation.