Objective: The Child Behavior Checklist is sometimes used to assess sleep disturbance despite not having been validated for this purpose. This study examined associations between the Child Behavior Checklist sleep items and other measures of sleep. Method: Participants were 122 youth (61% female, aged 7 through 17 years) with anxiety disorders (19%), major depressive disorder (9%), both anxiety and depression (26%), or a negative history of any psychiatric disorder (46%). Parents completed the Child Behavior Checklist and children completed a sleep diary, wore actigraphs for multiple nights, and spent 2 nights in the sleep laboratory. Partial correlations ([pr], controlling for age, gender and diagnostic status) were used to examine associations. Results: Child Behavior Checklist sleep items were associated with several other sleep variables. For example, "trouble sleeping" correlated significantly with sleep latency assessed by both diary (pr(113) = 0.25, p = 0.008) and actigraphy (pr(105) = 0.21, p = 0.029). Other expected associations were not found (e.g., "sleeps more than most kids" was not significantly correlated with EEG-assessed total sleep time: pr(84) = 0.12, p = 0.258). Conclusions: Assessing sleep using the Child Behavior Checklist exclusively is not ideal. Nonetheless, certain Child Behavior Checklist items (e.g., "trouble sleeping") may be valuable. Although the Child Behavior Checklist may provide a means of examining some aspects of sleep from existing datasets that do not include other measures of sleep, hypotheses generated from such analyses need to be tested using more rigorous measures of sleep. (Contains 3 tables.)