The Metropolitan Archdiocese of Ljubljana is a Latin ecclesiastical territory or diocese of the Catholic Church in Slovenia.

The Slovenian Catholic Church, or Catholic Church in Slovenia is part of the worldwide Catholic Church, under the spiritual leadership of the Pope in Rome. The 2018 Eurobarometer data shows 73.4% of Slovenian population identifying as Catholic that fell to 72.1% in the 2019 Eurobarometer survey. According to the Catholic Church data, the Catholic population fell from 78.04% in 2009 to 72.11% in 2019.