OBJECTIVES: Examining losses in childhood health-related quality of life associated with maternal smoking provides parents and policymakers another tool for the valuation of smoking cessation during pregnancy. This study advances previous work comparing childhood behavioral problems and maternal smoking by estimating the loss in quality-adjusted life years (QALYs) for the child.  METHODS: Using the National Longitudinal Survey of Youth 1979 Child and Young Adult data, this study retrospectively examined a cohort of 4114 mothers and 8668 children.  In addition to questions focusing on maternal smoking and general demographics, each survey included the Behavior Problems Index (BPI), a 28-item questionnaire with six subscales measuring childhood behavior problems (Antisocial Behavior, Anxiousness/Depression, Headstrongness, Hyperactivity, Immature Dependency, and Peer Conflict/Social Withdrawal). Responses to the BPI, completed by mothers with children ages 4-14, were summarized on a QALY scale using published preference weights. RESULTS: Children whose mothers smoked during pregnancy experience additional QALY losses of 0.181, on average, per year due to increased behavior problems. Boys suffered larger QALY losses associated with maternal smoking (0.242) compared to girls (0.119; p value = 0.021), regardless of age. Moreover, heavier smoking during pregnancy (i.e., 1 or more packs per day) was associated with larger QALY losses (0.282; p-value <0.001). CONCLUSIONS: These findings illustrate the burden of maternal smoking during pregnancy on child health, namely behavioral problems. These losses in QALYs may be incorporated into economic evaluations for smoking cessation interventions during pregnancy. Future research will investigate how maternal smoking following childbirth is associated with child QALYs.