The former Diocese of Roskilde (Danish: Roskilde Stift) was a diocese within the Roman-Catholic Church which was established in Denmark some time before 1022. The diocese was dissolved with the Reformation of Denmark and replaced by the Protestant Diocese of Zealand in 1537.^[1]

Today, the region once within the Diocese of Roskilde's jurisdiction is part of the Roman Catholic Diocese of Copenhagen and is divided (since 1922) between the Church of Denmark's Diocese of Copenhagen, the "new" Diocese of Roskilde and the Diocese of Helsingør (founded in 1961).

The episcopal see of the Bishop was Roskilde Cathedral but from 1167, when Bishop Absalon completed a new bishop's palace known as Absalon's Castle on the small island of Slotsholmen, he resided at the small town of Havn, which later became the present Danish capital Copenhagen.^{[citation needed]}

The diocese originally included both the island of Zealand and Scania (southern Sweden, then part of Denmark), but Scania was disjoined in 1060 and initially divided into the short-lived Diocese of Dalby and the Diocese of Lund, which absorbed the first and became the Metropolitan of (southern) Scandinavia.^{[citation needed]}

• c. 1022–1029/30 Gerbrand (da)
• c. 1030–late 1050s Avaco/Aage
• c. 1060–1073/74 William of Roskilde (da)
• 1074–1088 Svend Nordmand
• 1088–1124 Arnold
• 1124–1134 Peder
• 1134–1137 Eskild
• 1137–1138/39 Ricco/Rike
• 1139–1158 Asker/Asser
• 1158–1191 Absalon
• 1191–1214 Peder Sunesen [Wikidata]
• 1214/15–1224/25 Peder Jacobsen
• 1225–1249 Niels Stigsen
• 1249–1254 Jakob Erlandsen
• 1254–1277 Peder Bang
• 1278–1280 Stig (uncertainty regarding name)
• 1280–1290 Ingvar (uncertainty regarding name)
• 1290–1300 Johannes/Johan/Jens Krag
• 1301–1320 Oluf
• 1321–1330 Johan/Jens Hind
• 1330–1344 Johan/Jens Nyborg
• 1344–1350 Jacob Poulsen
• 1350–1368 Henrik Gertsen
• 1368–1395 Niels Jepsen Ulfeldt / Niels Jacobsen Ulfeldt
• 1395–1416 Peder Jensen Lodehat
• 1416–1431 Jens Andersen Lodehat
• 1431–1448 Jens Pedersen Jernskæg
• 1449–1461 Oluf Daa
• 1461–1485 Oluf Mortensen Baden
• 1485–1500 Niels Skave
• 1500–1512 Johan Jepsen Ravensberg
• 1512–1529 Lage Jørgensen Urne
• 1529–1536 Joachim Rønnow