Digital restoration refers to the preservation, backup, and distribution of cultural relics through digital technology so that they can still be protected and accessed in the case of loss of paper records or damage. The purpose of digital restoration was to provide a new way to protect cultural relics and to make it easier for people to better understand and appreciate cultural relics. In China, the initiative to promote the digital return of lost cultural relics in Dunhuang in 2021 aims to save these lost cultural relics through digital technology. The method of digital restoration included scanning, taking photos, compressing and packaging the cultural relics, and then spreading and sharing them through the Internet and other digital platforms. This will help people better understand and appreciate these cultural relics, and also provide a new way to protect cultural heritage.