The present study validated the use of the Korean version of the Reasons for Living Inventory for Adolescents (KRFL-A) in a group of 406 South Korean high school students. Confirmatory factor analysis confirmed the original 5-factor structure, and other psychometric properties demonstrated the usefulness of the KRFL-A as a measure of cognitive protective factors. Hierarchical regression analyses revealed that the KRFL-A total significantly moderated the impact of depressive symptoms on suicidal ideation. More specifically, the Family Alliance subscale among boys and the Peer Acceptance and Support subscale among girls moderated the relationships between depressive symptoms and suicidal ideation. This suggests that for Korean adolescents, gender-specific strategies are needed for more effective suicide interventions.