The Bulgarian Greek Catholic Church is a sui iuris ("autonomous") Eastern Catholic church based in Bulgaria. As a particular church of the Catholic Church, it is in full communion with the Holy See. The Church's liturgical usage is that of the Byzantine Rite in the Bulgarian language. The Church is organised as a single eparchy — the Bulgarian Greek Catholic Eparchy of Sofia.

Bulgarians are a nation and South Slavic ethnic group native to Bulgaria and its neighbouring region, who share a common Bulgarian ancestry, culture, history and language. They form the majority of the population in Bulgaria, while in North Macedonia, Ukraine, Moldova, Serbia, Romania, Hungary, Albania, Turkey and Greece they exist as historical communities.