In the recent twenty years, increasing researchers had used cognitive neuroscience approach to investigate emotion regulation. Although imaging studies have a very big advantage in spatial resolution, which can analyze the activation of emotional processing involved in various brain regions, the processing of emotion regulation is a dynamic process, which changes in a millisecond time window. Nowadays more and more research explores the individual brain responses to emotional processing by measuring event-related potentials (Event-Related Potentials, ERPs). Late Positive Potential (LPP) is a typical EEG component in the study of emotion regulation. It is a positive component, which appears evidence about 300-400ms after stimulus presentation at occipital to central recording sites. The dual role of reactivity and regulation effect during emotion regulation could be indexed by the modulation of LPP. The increased modulation LPP in response to emotional stimuli reflects individuals’ facilitated attention to emotional information during emotion regulation processing. Such increased modulation LPP is called the reactivity effect of emotion regulation. In addition, LPP is reduced following the use of different emotion regulation strategies. The decreased modulations of LPP index downstream processes deriving from increased activation of the frontal regions in later time window of emotion regulation and it is called the regulation effect of emotion regulation. Previous studies have pointed out that the decreased modulation of LPP appears evidence at posterior/superior recording sites with peak in the early time window (from 400 to 1000ms). With a spatial shifting over time, the topography of maximal LPP may shift from the posterior cortical activation, which is associated with the perceptual reactivity of the emotional stimuli to the prefrontal cortical region which is associated with the cognitive control. Recruitment of prefrontal cortical resources is associated with effective regulation and may result in the modulation of LPP. The spatial-temporal shifting patterns of LPP during the processing of emotion regulation have been proved in many developmental studies to explain the individual differences during development. For example, previous work has shown that toddlers exhibit enhanced modulations of LPP to negative emotional stimuli than neutral stimuli. This enhanced modulation has even been found in very young children. Researchers also examined the developmental changes of the spatial-temporal shifting patterns of LPP in different age range and try to figure out whether the development of specific brain regions (e.g., prefrontal cortex) are associated with the consequences of different regulatory strategies. For example, as the late LPP was the indicator of the involvement of cognitive resources and effective cognitive regulation, the age-related differences in the late LPP between children, adolescents and adults might be the possible reason why younger participants were less capable than adults in regulating emotions. To extent previous studies, future researchers should pay more attention to the examination of LPP patterns in the field of abnormal child development, the impact of brain development and hormones changes to the LPP patterns, and how individual differences associate with LPP modulations when regulating emotion. As a critical developmental window for the acquisition of mature regulatory processes, more research is needed to investigate to potential mechanism of emotion regulation development.