Of all psychiatric disorders, the disruptive behavior disorders (DBDs) are the most likely to predispose to substance dependence (SD). One possible underlying mechanism for this increased vulnerability is risky decision making. The aim of this study was to examine decision making in DBD adolescents with and without SD. Twenty-five DBD adolescents (19 males) with SD (DBD+SD), 28 DBD adolescents (23 males) without SD (DBD-SD) and 99 healthy controls (72 males) were included in the study. DBD adolescents with co-morbid attention deficit/hyperactivity disorder (ADHD) were excluded. Risky decision making was investigated by assessing the number of disadvantageous choices in the Iowa gambling task. DBD+SD made significantly more risky choices than healthy controls and DBD-SD. Healthy controls and DBD-SD did not differ on risky decision making. These results suggest that risky decision making is a vulnerability factor for the development of SD in a subgroup of adolescents with DBD without ADHD. (Contains 1 table and 2 figures.)