Death by suicide, and suicidal behaviors, are a significant public mental health problem, and individuals who are lesbian, gay, bisexual, transgendered and questioning (LGBTQ), may be at increased risk. Potential underlying mechanisms of this association are unknown, but may involve the impact of LGBTQ status on future orientation and mood. Our purpose was to determine the influence of sexual identity, sequentially, on cognitive and emotional functioning, and consequent relation to suicidal behavior. In a sample of 349 college students, we used serial mediation models to investigate the relation between self-identification as LGBTQ and suicidal behavior, with hope and hopelessness as first-order mediators and depression as a second order mediator. Supporting hypotheses, we found that LGBTQ status was related to less hope and greater hopelessness and, in serial fashion, to depressive symptoms and consequent suicidal behavior. Our findings may have clinical implications. Resolution of hopelessness and depression, and promotion of hopefulness, perhaps via Motivational Interviewing and Cognitive Behavioral Therapy strategies, such as goal-setting, may reduce suicidal risk in LGBTQ young adults.