According to recent models of addiction, negative affect plays an important role in maintaining drug dependence. The study investigated the effect of negative mood on attentional biases for smoking-related cues and smoking urge in cigarette smokers. Eye movements to smoking-related and control pictures, and manual response times to probes, were recorded during a visual probe task. Smoking urges and mood were assessed by self-report measures. Negative affect was manipulated experimentally as a within-participants independent variable; that is, each participant received negative and neutral mood induction procedures, in counterbalanced order in separate sessions, before the attentional task. There were two groups of participants: smokers and nonsmokers. Smokers showed (i) a greater tendency to shift gaze initially towards smoking-related cues, and (ii) greater urge to smoke when they were in negative mood compared with neutral mood. Manual response time data suggested that smokers showed a greater tendency than nonsmokers to maintain attention on smoking-related cues, irrespective of mood. The results offer partial support for the view that negative mood increases selective attention to drug cues, and urge to smoke, in smokers. The findings are discussed in relation to an affective processing model of negative reinforcement in drug dependence.