Culture has significant influence on various aspects of emotion including cognitive appraisal and expressive suppression. Previous studies found that cognitive reappraisal effectively reduced the negative emotional responding, while the emotion regulation efficiency of expression suppression strategy was controversial in different cultures. Expression suppression usually plays a negative role in individualistic culture, and is not completely an inappropriate regulation strategy in collectivistic culture. It is still unclear whether exists different emotion regulation strategies in different Chinese nationalities. Regulating negative emotion with expressive suppression and cognitive reappraisal and discovering the underlying mechanism in the Han and ethnic minority culture populations were therefore of great interest. The current experiment was a 2(ethnic cultures: Han, ethnic minority) × 4(emotion regulation strategies: neutral view, negative view, cognitive reappraisal, expressive suppression) mixed design. Thirty-two college students (16 were Han and 16 were ethnic minorities) were recruited in the current study. There were 4 blocks which consisted of 2 viewing blocks and 2 regulating blocks, and each block included 60 pictures that were taken from Chinese Affective Picture System (CAPS). In viewing blocks, participants just attended to neutral or negative pictures; whereas, in regulating blocks, participants were instructed to intentionally suppress the expression of emotional responses to pictures or imagine themselves as an objective observer to the situation depicted. Event-Related Potentials (ERPs) were recorded during the presentation of pictures. By the end of each block, subjects were required to rate their mood state and the success of suppressing, reappraising the pictures by a self-report scale. Behavioral results showed a significant difference in the level of self-reported negative emotions among the three strategies (negative view, cognitive reappraisal, expressive suppression), F(2,60)=174.65，p<.01，η2=.85. The subjective emotional experience of the expression suppression was higher than the cognitive reappraisal. The interaction between ethnic culture and emotion regulation strategy was significant, F(2,60)=8.22，p<.01，η2=.22. The cognitive reappraisal and expression suppression could significantly reduce the negative emotional experience of Han and ethnic minority subjects, while the emotion regulation effect of expressive suppression on ethnic minority subjects was worse than Han. In electrophysiological results, negative emotional pictures induced greater P2 amplitudes than neutral pictures, and expression suppression induced greater P3 amplitudes than cognitive reappraisal in frontal-central. Late Positive Potential (LPP) showed more pronounced amplitudes during expressive suppression relative to cognitive reappraisal. More importantly, there was a significant interaction effect of ethnic culture and emotion regulation strategy in 900~1200ms LPP window, F(3,90)=3.77，p<.05，η2=.12. The cognitive reappraisal and expressive suppression significantly reduced the negative emotion-related LPP amplitudes of Han subjects, and regulation effects of two strategies had no significant difference. However, cognitive reappraisal significantly reduced the negative emotion-related LPP amplitudes of ethnic minority subjects, but not expressive suppression. In conclusion, the effect of emotion regulation varies in different ethnic cultures. Individuals with Han culture can effectively reduce negative emotion by using expressive suppression strategy, while individuals with ethnic minority culture are more suitable for cognitive reappraisal strategy to regulate negative emotion.