Being able to regulate emotions is critical to coping with stress. Stress has also been shown to reduce emotion regulation ability; specifically, stress-based HPA axis activation reduces top-down control of emotion regulation. Reducing HPA axis activation could therefore allow a person to better utilize emotion regulation strategies. Slow-paced breathing can activate the parasympathetic nervous system through increasing vagal tone. In this study, we examined whether a short bout of slow-paced breathing could acutely improve emotion regulation in young adults. Participants were asked to regulate their emotional reactions to negatively valenced images using cognitive reappraisal to either increase, decrease, or maintain the emotional intensity. In the experimental condition, participants completed a 3-minute voluntary breath control exercise prior to the experimental trials. In the control condition, participants completed the experimental trials without a breathing exercise. This was a within-subjects design. An acute bout of slow-paced breathing prior to the emotional experience reduced negative valence and arousal ratings in response to negative images. Participants also reported greater success at emotion regulation following the breathing compared to the control condition. Therefore, slow-paced breathing may be an effective tool to acutely enhance emotion regulation abilities, possibly through the increase in parasympathetic nervous system activation.