- Graham Chapman
- King Arthur / Voice of God / Middle Head / Hiccoughing Guard
- John Cleese
- Second Swallow-Savvy Guard / The Black Knight / Peasant 3 / Sir Launcelot the Brave / Knight of Camelot / Taunting French Guard / Tim the Enchanter
- Eric Idle
- Dead Collector / Peasant 1 / Sir Robin the Not-Quite-So-Brave-as-Sir Launcelot / Knight of Camelot / First Swamp Castle Guard / Concorde / Roger the Shrubber / Brother Maynard
- Terry Gilliam
- Patsy / Green Knight / Knight of Camelot / Old Man from Scene 24 (Bridgekeeper) / Sir Bors / Animator / Gorilla Hand
- Terry Jones
- Dennis's Mother / Sir Bedevere / Knight of Camelot / Left Head / Prince Herbert / Voice of Cartoon Scribe
- Michael Palin
- First Swallow-Savvy Guard / Dennis / Peasant 2 / Right Head / Sir Galahad the Pure / Knight of Camelot / Narrator / King of Swamp Castle / Brother Maynard's Brother / Leader of The Knights Who Say NI!
- Connie Booth
- The Witch
- Carol Cleveland
- Zoot / Dingo
- Neil Innes
- First Monk / Singing Minstrel / Page Crushed by the Rabbit / Peasant #4
- Bee Duffell
- Old Crone
- John Young
- Dead Body / Historian Frank
- Rita Davies
- Historian's Wife
- Avril Stewart
- Dr. Piglet
- Sally Kinghorn
- Dr. Winston
- Mark Zycon
- Prisoner
- Elspeth Cameron
- Girl in Castle Anthrax
- Mitsuko Forstater
- Girl in Castle Anthrax
- Sandy Johnson
- Knight of Ni / Villager at Witch Burning / Musician at Wedding / Monk / Knight in Battle
- Sandy Rose
- Girl in Castle Anthrax
- Romilly Squire
- Musician at Wedding / Villager at Witch Burning
- Joni Flynn
- Girl in Castle Anthrax
- Alison Walker
- Girl in Castle Anthrax
- Loraine Ward
- Girl in Castle Anthrax
- Anna Lanski
- Girl in Castle Anthrax
- Sally Coombe
- Girl in Castle Anthrax
- Vivienne MacDonald
- Girl in Castle Anthrax
- Yvonne Dick
- Girl in Castle Anthrax
- Daphne Darling
- Girl in Castle Anthrax
- Fiona Gordon
- Girl in Castle Anthrax
- Gloria Graham
- Girl in Castle Anthrax
- Judy Lamb
- Girl in Castle Anthrax
- Tracy Sneddon
- Girl in Castle Anthrax
- Sylvia Taylor
- Girl in Castle Anthrax
- Joyce Pollner
- Girl in Castle Anthrax
- Mary Allen
- Girl in Castle Anthrax
- Iain Banks
- Knight in Battle
- Julian Doyle
- Police Sergeant
- Margarita Doyle
- Peasant
- Charles Knode
- Camp Guard / Robin's Minstrel (uncredited)
- Zack Matalon
- Guard who Falls into Barrels
- Scott Mike
- Bash (Mudfighter
- William Palin
- Sir Not-Appearing-in-this-Film
- Monty Python
- Themselves
- Tom Raeburn
- Guard Eating Apple
- Brian Ross
- Biff (Mudfighter)
- Roy Forge Smith
- Inspector End of Film
- John Thornton
- Dancing Knight
- Maggie Weston
- Page-turner