The task persistence construct has previously been measured primarily behaviorally (e.g., with a mirror-tracing task, or breath holding), and only in adults. It has been shown to differentiate between adult smokers and non-smokers and to predict smoking cessation in adult smokers trying to quit. This theory-based analysis is the first to examine task persistence in adolescent smokers and to examine a two-item, internally consistent, self-report measure of task persistence. Results indicate that task persistence is greater among adolescent non-smokers as compared to adolescent current smokers, and those planning to quit smoking as compared to those with no plans to quit. Contrary to hypotheses, task persistence was not found to be related to prior successful attempts to quit smoking. Our results suggest that a brief, self-report measure of task persistence may be a methodologically sound, practical clinical tool for this population.