ABSTRACT. Objective: Despite the commonly observed comorbidity of alcohol and tobacco use disorders and years of research, the mechanism underlying concurrent use of alcohol and tobacco is not yet clear. In this study, we used functional magnetic resonance imaging (fMRI) to investigate the relationship between brain responses to alcohol and smoking cues in 45 subjects with episodic drinking and regular smoking. Method: fMRI data were collected from two studies performing an alcohol-craving task and a smoking-craving task. First, we identifi ed brain voxels signifi cantly activated for both substance cues and then associated the activation of these voxels with various alcohol-and nicotine-dependence measures. Signifi cant clusters (cluster-wise p < .05) correlated with behavioral assessments were extracted, and clusters identifi ed from both cues were compared. Results: The association tests with various dependence scores showed that the loss of behavioral control subcategory in the Alcohol Dependence Scale was signifi cantly correlated with brain activation of the posterior cingulate cortex (PCC) and right posterior insula regardless of cue types. Conclusions: Our fi ndings suggest that the PCC and right posterior insula, each playing a role in the salience network, are affected signifi cantly by impaired control for alcohol and in turn infl uence brain responses to not only alcohol but also smoking cues, providing insight to neuronal mechanisms for concurrent use or comorbidity of alcohol and nicotine dependence. (J. Stud. Alcohol Drugs, 75, 808-816, 2014)