Mindfulness is typically defined as nonjudgmental attention to experiences in the present moment. Mindfulness includes two components: the first component is the regulation of attention to maintain it on the immediate experience and the second component involves approaching one’s experiences with curiosity, openness, and acceptance. A large body of research has documented the efficacy of mindfulness training in the treatment of clinical disorders, including anxiety, depression, substance abuse, eating disorders, and chronic pain. Until recently, not only has mindfulness training successfully been used in the treatment of disorders but it has also been shown to produce positive effects on psychological well-being and to improve the emotional regulation ability. Thus, it has been showed largely that mindfulness training influenced emotional processing. The scientific study of mindfulness has viewed mindfulness as an attentional state which can be fostered through training. Mindfulness training research entails training mindfulness na?ve participants to adopt a mindful attentional stance (3 minutes to 1 hour) while completing emotion tasks, or examining how brief (4 days to 10-weeks) mindfulness training or long (1 year longer) mindfulness training impacts emotional processing. Thus, the article systematically reviewed the moderating effect of mindfulness training on emotional processing, from the training level (including temporary mindfulness training, short mindfulness training, and long mindfulness training) perspectives. In the article, we first investigated the relationship of temporary mindfulness training and emotional processing. Second, we examined the relationship of short mindfulness training and emotional processing. Third, we exploited the relationship of long mindfulness training and emotional processing. Finally, we raised some questions which need to be done in the future. Mindfulness training research can be categorized by participants’ level of mindfulness training: temporary mindfulness training, short mindfulness training, and long mindfulness training. A lot of research showed that mindfulness training improved individual emotion regulation, and then increased individual subjective well-being and the quality of life. First, studies of Temporary mindfulness using meditation na?ve participants instruct participants with no previous mindfulness training to adopt a mindful attentional stance. Research showed that temporary mindfulness training was associated with greater widespread prefrontal cortical activation (especially left prefrontal cortex), and reduced amygdala activity, which then influenced emotional processing. Thus, temporary mindfulness training is an effective method of emotion regulation. In contrast, short mindfulness training increased individual mindfulness consciousness, and improved individual emotional regulation. From the neural research, short mindfulness training increased the activation in the attention-related cortical regions and the left prefrontal cortex, and reduced amygdala activity. For long mindfulness training, as the training time increased, long mindfulness training increased mindfulness consciousness, and improved individual emotional regulation. Especially, long training of Open monitoring meditation could better facilitate emotional processing. In conclusion, individuals can improve individual emotional regulation, and then increase individual subjective well-being and the quality of life through mindfulness training, and mindfulness training has been proved to have significant effects on the interventions for psychological and physical disorders. Future studies should focus on the relationship between mindfulness training and dispositional mindfulness, investigate how mindfulness training types and mindfulness training time contribute to emotional processing, and further clarify the relationship between mindfulness meditation training relates to brain lateralization.