Its patron saints are Francis Xavier and Catherine of Siena, and its motto is Scientia et Virtus (Knowledge and Virtue).

[2] It was established on January 23, 1576, by the edict of Pope Gregory XIII, on vast territory split off from Roman Catholic Diocese of Malacca.

It originally covered China, Japan, Vietnam and the Malay Archipelago, with the exception of the Philippines.

It gradually lost most of its territory, in and around continental China: It was made exempt in 1975, following Portugal's loss of sovereignty over Goa, its former metropolitan.

It now only administers Macau alone, the last regions outside Macau under its administration were the parishes of Saint Joseph in Singapore (re-united with the Roman Catholic Archdiocese of Singapore c. 1972) and St. Peter's Church in Malacca (now as part of Roman Catholic Diocese of Malacca-Johor), which separated from the Diocese of Macau in 1981. from 1641 to 1668, no bishops were named due to the Portuguese Restoration War between Spain and Portugal[9] The diocese is divided in: The following schools are directly operated by the diocese: There are other Catholic schools in Macau which are operated by Catholic orders.