The Roman Catholic Archdiocese of Alba Iulia (Latin: Archidioecesis Albae Iuliensis); Hungarian: Gyulafehérvári Római Katolikus Érsekség) is a Latin Church archdiocese in Transylvania, Romania.

It was established as a bishopric, the diocese of Transylvania also called Erdély (in Hungarian), or Karlsburg alias Siebenbürgen (in German), in 1009 by King Stephen I of Hungary and was renamed as the diocese of Alba Iulia on 22 March 1932.

It was raised to the rank of an archdiocese by Pope John Paul II on 5 August 1991. It is exempt, i.e. directly subordinate to the Vatican, while the other Romanian dioceses form the Ecclesiastical Province of Bucharest.

This list is incomplete; you can help by adding missing items. (September 2024)

Bishops

• (?) Franco (1071–1081)
• Simon (1111–1113)
• Peter (1134)
• Baranus (1139)
• Walter (1156–1157/8)
• Vilcina (1166–1169)
• Paul (1181)
• Adrian (1192–1201)
• William (1204–1221)
• Raynald of Belleville (1222–1241)
• Artolf (1244–1245)
• Gallus (1246–1269)
• Peter Monoszló (1270–1307)
• Benedict (1309–1319)
• Demetrius (1368–1376)
• Goblinus (1376–1386)
• János Statileo (1534–1542)
• Pál Bornemissza (1553–1556)
• Demeter Naprágyi (1597–1605)
• Ignác Batthyány (1780–1798)
• Sándor Rudnay (1815–1819)
• Lajos Haynald (1852–1863)
• Áron Márton (1938–1980)
• Lajos Bálint (1990–1991)

Archbishops

• Lajos Bálint (1991–1993)
• György Jakubinyi (1994–2019)
• Gergely Kovács (since 2019)

• György-Miklós Jakubinyi (1990–1994), appointed Archbishop here
• József Tamás (1996–2019)
• László Kerekes (since 2020)

The archdiocese covers Transylvania proper—the counties of Alba, Bistrița-Năsăud, Brașov, Cluj, Covasna, Harghita, Hunedoara, Mureș, Sălaj and Sibiu.

The cathedral episcopal see is St. Michael's, in Alba Iulia city. It also has a minor basilica in Șumuleu Ciuc.

11% of the inhabitants are Roman Catholic, with concentrations in parts of Harghita and Covasna counties. Catholic adherents are predominantly ethnic Hungarians.

• (in Hungarian) Official site
• GigaCatholic, listing the episcopal incumbents

46°04′03″N 23°34′12″E / 46.0676°N 23.5700°E / 46.0676; 23.5700