Xu Guangqi was one of the earliest Catholics towards the end of Ming Dynasty. He was also a scientist, and a translator.

Born in Shanghai, Xu passed the national examination and became a Scholar. On his way to Beijing, Xu met Matteo Ricci. In 1603, he was baptized by Jean de Rocha, and became a Christian with the Christian name Paul. Xu became a high ranking official in 1604 and studied under Ricci. On his way back to Shanghai to attend his father's funeral, Xu dropped by Nanking and urged Lazaro Cattaneo to preach in his hometown. They held church meetings in Xu's house and baptized his family members and friends. Xu set up astronomy instruments in Beijing in 1610 and established Catholic schools in 1616.

In 1625, Xu resigned from is position, returned to Shanghai and wrote the 'Book of Agriculture.' Xu regained his position in 1628 and wrote the 'Book of Annals of Zong Zhen' with Li Zhizao. He also translated many books written by Ricci.