Replicas of Marian images, especially the Salus Populi Romani, played an important role in the conversion of Chinese literati and commoners to Christianity. This article examines the diffusion of replicas of the Salus Populi Romani in the Ming Empire during the late sixteenth century, including both copies produced in situ and those coming from Europe. It focuses particularly on the role of miraculous and conversion tales related to the vision of Salus Populi Romani reproductions. This paper also focuses on the renowned conversion of the Chinese literatus (Paul) Xu Guangqi 徐光啓 (1562-1633) as it has been narrated by the Jesuit missionaries and the controversial role in his conversion played by a Marian devotional image. Conversely, this piece takes into consideration the role played by the production and reproduction of Marian devotional images in the Ming dynasty cultural context, including a new change in the enthusiasm in China for "Western" artworks and the wide diffusion of Roman Catholicism through "European" and "European-like" devotional images.