Diocese of Santa Giusta
The Diocese of Santa Giusta, formerly Othoca, was a Roman Catholic diocese in Santa Giusta, Sardinia. The bishop's seat was in the former Santa Giusta Cathedral, now a minor basilica.
The diocese was established at an unknown date in the 11th century. Its earliest known bishop was Augustinus (1119). The diocese was suppressed in 1503, and its territory was assigned to the Archdiocese of Oristano (Arborea).