Based on analyses of reports about Yi ethnic people in Liangshan, Sichuan Province from 10 mainstream media on Weibo, and on empirical studies on Yiethnic young people's use of smart phones, discrepancies between the image of Yi peoplepresented by mainstream media and the imageself-painted by Yi ethnic young people on social media could be found. New media plays an important role in rendering such differences through generation of media memories. Smartphones have endowed Yi ethnic young people with new ways of culture practice, so that they could create new memorieswith more vitality on the basis of their original collective memory. Nevertheless, new media memories also cause crises such as ethnic memoryfragmentation, digitalamnesia and excessive entertainment. To solve these problems, several countermeasures have been suggested: Yi ethnic young people should actively cooperate with external resources, mobilize and revise their narratives, and reshape their collective memories, so as to promote the sustainability and prosperity of their ethnic culture.