The Basilica di Sant'Antioco of Bisarcio is a countryside church near Chilivani, a frazione of Ozieri, Sardinia, Italy. Located on an isolated volcanic hill, it is one of the largest Romanesque churches in Sardinia.

A Catholic diocese with seat in Bisarcium, in what was then the giudicato of Torres or Guisarchium is documented from 1065 to 1503, when it was annexed to that of Alghero. A first cathedral was built here in the late 11th century, but was later damaged by a fire, so that a document from 1139 suggests that the bishop had moved his seat to Ardara. The new cathedral was finished in 1174, when the two storey portico on the façade was completed. Today scanty remains of the medieval village of Bisarcio remain.