Relatively little is known about smoking cessation self-efficacy and outcome expectations for quitting smoking in adolescent smokers. In this study, we created measures of these two constructs and conducted factor analyses with data from a diverse sample of 1126 adolescent smokers. Results yielded a two-factor solution for the self-efficacy measure, and a four-factor solution for the outcome expectations scale. In a subset of the original sample (n=515), we re-administered the measures one year later and also examined the longitudinal associations between the baseline sub-scale scores and cigarettes smoked per week at follow-up. Results revealed significant relationships between the negative affect sub-scales of the self-efficacy and outcome expectations measures and weekly smoking level. These associations remained when adjusting for baseline smoking level and other sub-scales. The findings lend support for the possible role of affect regulation in smoking reduction in adolescents.