Objective To evaluate the longitudinal relationships between unit cohesion, Army leader behaviors, and subordinate suicidal/death ideation. Recent cross-sectional research indicates that subordinates who perceive that their leaders instill a sense of purpose regarding military service demonstrate less frequent suicidal ideation. Method Five hundred fifty-nine soldiers completed self-report measures of perceptions of leadership behaviors, unit cohesion, and suicidal/death ideation during deployment as well as one and three months following deployment. Latent change score modeling was conducted to evaluate the course and direction of study variables as well as the relationship between them. Results Although lower levels of suicidal/death ideation were related to leader-provided purpose, leader-provided meaning, and unit cohesion at baseline, only leader-provided purpose and unit cohesion prospectively predicted changes in suicidal/death ideation. Conclusions Consistent with the goal of military leadership to augment effective clinical interventions that reduce suicide risk, prevention programs that reach a broader population of personnel should be considered. Enhanced leadership training may be an important primary prevention tool to reduce suicide risk that warrants further research.