The process model of emotion regulation was proposed by Gross (1998), who held that emotion regulation generated during emotion producing process. The process was that individual influenced the emotional occurrence, experience and expression. Emotion regulation, especially for negative emotional adjustment, is an important cognitive function for human to adapt to the environment. Reappraisal and distraction are generally considered as effective cognitive emotion regulation strategies, which have attracted much attention from researchers. But several problems still exist in the research: the cognitive emotion regulation processing activities and emotional response are always confused; the attention to the emotional response is lack when the same or similar negative stimuli appear again after regulation; a lot of research is dependent on the self report of feeling. On that basis, we adopt the event-related potentials technique (ERPs), separated the cognitive emotion regulation processing activities and emotional response, and paid attention to the emotional response when the same or similar negative stimulus appeared again after regulation. Fifteen participants of university students were instructed to complete the task of emotion regulation (reappraise, distract, and simply attend) to negative emotional pictures. Electroencephalogram (EEG) signals were recorded using a 64-electrode elastic cap and the Neuroscan ERP workstation. Based on the overall average map and the research literatures, we divided the ERP components by the time windows in which they occurred: in the emotion induction phase, we analysed the LPP among 300~1000ms on the Pz electrode; in the phase of negative emotional pictures appearing again, we analysed the LPP among 300~2000ms (and 8 little time windows: 300~500 ms, 500~700 ms，700~900 ms，900~1100 ms，1100~1300 ms，1300~1500 ms，1500~1700 ms，1700~2000 ms)on the Pz electrode. Repeated measure ANOVAs were conducted on the behavioural data and the measurements derived from ERP waveforms. The results showed that the strength of negative emotional experience and LPP amplitude （300-1300ms）after reappraisal were lower than these of simple attention; after distraction, the participants’ negative emotional experience strength became lower than that of attention condition, but the LPP amplitude enhanced. The results demonstrate that the influences of reappraisal and distraction to negative emotional experience and brain electrical activity are different. When the negative emotional pictures show again, cognitive reappraisal is more effective than distraction. Our discoveries also provide electrophysiological evidences for the research on the comparison of reappraisal and distraction.