Our aim was to investigate the association between alcohol dependence and suicidal behavior among adolescent girls and boys suffering from conduct disorder (CD). The original study sample consisted of 387 adolescents (age 12-17) admitted to psychiatric inpatient care between April 2001 and May 2005. DSM-IV-based psychiatric diagnoses and variables measuring suicidal behavior were obtained from the Schedule for Affective Disorders and Schizophrenia for School Aged Children--Present and Lifetime (K-SADS-PL). Of the total study population, 59 adolescent girls and 82 boys had CD according to DSM-IV criteria. Of all adolescents with CD, 24 (40.7%) girls and 24 (29.3%) boys were suffering from alcohol dependence. Among girls with CD, alcohol dependence increased the risk for suicide attempts up to 3.8-fold (95% CI 1.1-13.4). Among boys with CD, alcohol dependence increased the risk for life-threatening suicide attempt over nine-fold (95% CI 1.2-80.1). In addition, the risk for self-mutilative behavior was as high as 3.9-fold (95% CI 1.1-13.8) among girls and 5.3-fold (95% CI 1.1-26.5) among boys. The results indicate that, among adolescents suffering from CD, the risk of suicidal behavior is considerably increased by co-morbid alcohol dependence, which should therefore be carefully taken into account in clinical work.