Objective: The Internet represents a new and widely available forum for gambling. However, relatively few studies have examined Internet gambling in adolescents. This study sought to investigate the correlates of at-risk or problem gambling in adolescents acknowledging or denying gambling on the Internet. Method: Survey data from 2,006 Connecticut high school student gamblers were analyzed using chi[superscript 2] and logistic regression analyses. Results: At-risk/problem gambling was found more frequently in adolescent Internet gamblers than in non-Internet gamblers. Compared with at-risk/problem gambling in the non-Internet gambling group, at-risk/problem gambling in the Internet gambling group was more strongly associated with poor academic performance and substance use (particularly current heavy alcohol use; odds ratio 2.99; p = 0.03) and less strongly associated with gambling with friends (odds ratio 0.32; p = 0.0003). At-risk/problem gambling in the Internet and non-Internet gambling groups, respectively, was associated at p less than 0.05, each with multiple adverse measurements including dysphoria/depression (odds ratios 1.76 and 1.96), getting into serious fights (odds ratios 2.50 and 1.93), carrying weapons (odds ratios 2.11 and 1.90), and use of tobacco (odds ratios 2.05 and 1.88 for regular use), marijuana (odds ratios 2.02 and 1.39), and other drugs (odds ratios 3.24 and 1.67). Conclusions: Clinically, it is important to assess for teenagers' involvement in Internet gambling, particularly because adolescent at-risk/problem Internet gambling appears specifically associated with nonpeer involvement, heavy alcohol use, and poor academic functioning. (Contains 5 tables.)