Antonio Dominic Ubach (1835–1907) was a Spanish Roman Catholic priest and advocate for the education of Native Americans in San Diego, California, during the late 19th century.

Ubach, a native of Catalonia, in Spain, was the first priest appointed to serve Mission San Diego de Alcalá after California's annexation by the United States.

At that time, there was no efforts made by the U.S. government for the education of Native Americans, and for nearly twenty years, he had to rely on private resources, mostly the Presbyterian mission office.

By the time they ceased to provide aid, a national office of the Catholic Church dedicated to the colonization of Blacks and Native Americans had been established.

For this work, three schools were eventually founded, and were run by the Sisters of St. Joseph of Carondelet, whom Ubach met when they passed through San Diego on their way to Arizona, their first establishment in the region.