Knowing which factors predict the use of psychostimulant drugs among youths is important for designing preventive programs and the identification of youths with the highest probability of use, to avoid some of the problems that can be derived from it. The purpose of this study is to examine the relationship between perceived availability, risk perception, personality traits, antisocial personality patterns, and use of other substances in the prediction of psychostimulant use. The sample was composed by 1,177 youths (584 males and 593 females) aged 14 to 25 in Spain, recruited randomly, stratified by lifetime use- non use of psychostimulants (cocaine or ecstasy). The path which best predicts psychostimulant use is: Personality traits-legal substance use-cannabis use-psychostimulant use. The next path is: Personality traits-antisocial personality patterns-psychostimulant use. Risk perception and perceived availability were significant in the prediction, but made a smaller contribution. The results of this study suggest that the model evaluated can predict psychostimulant use in youths. This model can be seen as a useful tool for developing preventive strategies and for identifying those youths that are at risk for problems related to drug use.