Adolescent gambling is a serious and increasingly common problem. Studies in adults have found several within-and between-person associations between personality and gambling. We aim to extend these findings to a sample of adolescents selected for gambling behavior. Participants consisted of a racially diverse sample of adolescents between the ages of 13 and 17 (n = 227). We collected self-reported information on normal-range personality traits, sensation-seeking, and gambling frequency, severity, and motives in an online survey. Normal-range personality traits were not correlated with gambling, but trait sensation-seeking was positively correlated with gambling. Latent class analyses showed that classes of adolescent gamblers may be differentiated based on personality trait patterns, although these classes were not differentiated on gambling severity or frequency. Finally, in hierarchical analyses, six homogenous components representing the five normal-range personality traits and sensation-seeking accounted for maximum variance in gambling outcomes. In this model, components representing sensation-seeking and conscientiousness were the only significant unique predictors of gambling-related outcomes. Our findings suggest that subgroups of adolescent gamblers may be distinguished based on personality trait patterns before the emergence of problematic gambling. In other words, personality differences may reflect an early predisposition to divergent pathways to adolescent gambling. Our findings concur with previous work and underscore the importance of sensation-seeking as a particularly important risk factor of initiation and escalation of adolescent gambling.