BACKGROUND Research suggests a strong association between negative affect (NA) and smoking. However, little is known about the association between NA and smoking among individuals who switch to reduced-nicotine cigarettes. The goal of this study was to examine the extent to which cigarette nicotine content moderates the relationship between NA and smoking over time. METHODS Seven hundred and seventeen participants, 237 in the normal nicotine content (NNC; 15.8 mg/g and usual brand) cigarette group and 480 in the very low nicotine content (VLNC; 2.4 mg/g nicotine or less) cigarette group, participated in a randomized trial that examined the effects of cigarette nicotine content on smoking behavior over 6 weeks. We used parallel process latent growth curve modeling to estimate the relationship between changes in NA and changes in the numbers of cigarettes smoked per day (CPD), from baseline to 6 weeks, as a function of cigarette nicotine content. RESULTS The relationship between NA and investigational CPD reduced over time for those in the VLNC group, but not for those in the NNC group. There was no significant relationship between change in PA and CPD over time for either cigarette group. CONCLUSIONS Smoking VLNC cigarettes disrupts the relationship between smoking and negative affect, which may help reduce nicotine dependence. CONCLUSIONS This study suggests that the association between NA and smoking behavior is reduced over time among those that smoked reduced-nicotine content cigarettes. This provides additional evidence that smoking reduced-nicotine content cigarettes may help reduce nicotine dependence.