Poor sleep quality and tobacco use are common and co-occurring problems, although the mechanisms underlying the relations between sleep disturbance and smoking are poorly understood. Sleep disturbance lowers odds of smoking cessation success and increases odds of relapse. One reason may be that sleep loss leads to emotion dysregulation, which in turn, leads to reductions in self-efficacy and quit-related problems. To address this gap, the current study examined the explanatory role of emotion dysregulation in the association between sleep disturbance and smoking in terms of (1) self-efficacy for remaining abstinent in relapse situations, (2) the presence of a prior quit attempt greater than 24 hours, and (3) the experience of quit-related problems among 128 adults (Mage=40.2; SD=11.0; 52.3% female) seeking treatment for smoking cessation. Results suggested that increased levels of sleep disturbance are related to emotion dysregulation which, in turn, may lead to lower levels of self-efficacy for remaining abstinent, more quit-related problems, and being less likely to have had a quit attempt of 24 hours or greater. Further, these indirect effects were present above and beyond variance accounted for by theoretically-relevant covariates (e.g., gender and educational attainment), suggesting that they may maintain practical significance. These findings suggest that this malleable emotional risk factor (emotion dysregulation) could serve as a target for intervention among those with poor sleep and tobacco use.