BackgroundAdolescent suicide is regarded as a serious phenomenon that affects the well-being of the youth. This study aims to investigate the prevalence of suicidal behaviours and their association with physical/psychological harm and substance use in a nationally representative sample of adolescents in Grades 7–12 in Lebanon.MethodsData from the latest Global School-Based Student Health Survey conducted in 2017 were used in this study. The prevalence and correlates of suicidal ideation and suicide attempts among those who had considered committing suicide, at least once, were explored.ResultsAn estimated 13.45% of Lebanese adolescents, particularly females in Grades 7–12 had considered suicide at least once in the past 12 months. More importantly, almost half of them had attempted it at least once in the past 12 months. Those who frequently felt lonely or worried (previous year), were involved in physical fights or assaults (previous year), had been verbally or physically bullied (previous month), had missed more school days, experienced food insecurity, and had a history of substance abuse (marijuana, amphetamine, alcohol, and tobacco products) were more likely to exhibit suicidal behaviours. Parental support and older age at drug initiation appeared to be protective factors.DiscussionThe findings characterise the correlates of suicidal behaviours among school-going Lebanese adolescents and determine the attributes of the risk group susceptible to engaging in suicide attempts. Future interventions and policies should consider these attributes when monitoring target groups, particularly those with the alarming behaviours identified in this study. In addition, awareness campaigns that engage all stakeholders, particularly parents, should be prioritised by the authorities.