| Graham Chapman |
King Arthur/Voice of God/Middle Head/Hiccoughing Guard |
| John Cleese |
Second Swallow-Savvy Guard/The Black Knight/Peasant 3/Sir Lancelot, the Brave/Taunting French Guard/Tim the Enchanter |
| Eric Idle |
Dead Collector/Peasant 1/Sir Robin the Not-Quite-So-Brave-as-Sir Launcelot/First Swamp Castle Guard/Concorde/Roger the Shrubber/Brother Maynard |
| Terry Gilliam |
Patsy/Green Knight/Old Man from scene 24 /Sir Bors/Animator/Gorrilla Hand |
| Terry Jones |
Dennis's Mother/Sir Bedevere/Left Head/Voice of Cartoon Scribe/Prince Herbert |
| Michael Palin |
First Swallow-Savvy Guard/Dennis/Peasant 2/Right Head/Sir Galahad the Pure/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 |
King Arthur and his knights embark on a low-budget search for the Grail, encountering many very silly obstacles.