BACKGROUND: To assess associations among young adults between suicidal ideation in the previous year and adverse childhood events, occupation, education, tobacco use, alcohol abuse, cannabis use in the previous month, illicit drug use, sexual orientation and activity, depression, physical violence in the previous year, and lifetime forced sexual intercourse. METHODS: A subsample of 4075 French adults aged 18-30 years was drawn from a random national telephone survey in 2005. Major depressive episode and alcohol abuse were assessed using CIDI-SF and AUDIT-C (score above 4). Data were analysed with logistic regressions. RESULTS: Suicidal ideation affected 5.7% of men and 4.9% of women. Among men depression had the highest adjusted odds ratio (ORa=8.06, 5.07-12.79), followed by homosexual intercourse (3.37, 1.62-7.04), absence of sexual activity (2.83, 1.80-4.44); ORa between 1.6 and 2.0 were observed for living alone, daily tobacco smoking, being unemployed, serious health event concerning the father, age 26-30 and bad relationships between parents. Among women, depression had the highest ORa (7.60, 4.70-12.29), followed by lifetime experience of forced sexual intercourse (5.37, 2.89-9.96), having consumed illicit drugs other than cannabis (4.01, 1.48-10.89); ORa between 1.7 and 2.5 were observed for living alone, being unemployed, bad relationship between parents and age 26-30. LIMITATIONS: Cross-sectional survey, sexual orientation inferred from sexual activity. CONCLUSION: Suicide prevention should integrate the fact that besides depression, unemployment, family history, age, and sexual activity and orientation are specific risk factors among men, whereas illicit drug use, violence and forced sexual intercourse are more important among women.[résumé auteur]