 | Gene Hackman als Harry Caul |
 | John Cazale als Stan |
 | Allen Garfield als William P. 'Bernie' Moran |
 | Frederic Forrest als Mark |
 | Cindy Williams als Ann |
 | Michael Higgins als Paul |
 | Elizabeth MacRae als Meredith |
 | Teri Garr als Amy Fredericks |
 | Harrison Ford als Martin Stett |
 | Mark Wheeler als Receptionist |
 | Robert Shields als The Mime |
| Phoebe Alexander als Lurleen |
 | Ramon Bieri als Man at Party (uncredited) |
 | Gian-Carlo Coppola als Boy in Church (uncredited) |
 | Robert Duvall als The Director (uncredited) |
| Richard Hackman als Confessional Priest / Security Guard (uncredited) |
 | Billy Dee Williams als Man in Yellow Hat (uncredited) |
| Francis Ford Coppola | Director |
| Francis Ford Coppola | Producer |
| David Shire | Original Music Composer |
| Richard Chew | Editor |
| Jennifer Shull | Casting |
| Dean Tavoularis | Production Design |
| Doug von Koss | Set Decoration |
| Aggie Guerard Rodgers | Costume Design |
| Clark L. Paylow | Production Manager |
| Ted Moehnke | Creature Design |
| Buddy Joe Hooker | Stunts |
| Walter Murch | Sound Designer |
| Bill Butler | Director of Photography |
| Haskell Wexler | Director of Photography |
| Fred Roos | Co-Producer |
| Mona Skager | Associate Producer |
| Nathan Boxer | Sound Recordist |
| Michael Evje | Sound Recordist |
| Art Rochester | Sound Recordist |
| Howard Beals | Sound Effects Editor |
| Pete Horner | Sound Editor |
| Charles Myers | Assistant Director |
| Ted Moehnke | Property Master |
| Walter Murch | Sound Re-Recording Mixer |
| Joe Dunnigan | Gaffer |
| Doug Finn | Gaffer |
| Ralph Gerling | Camera Operator |
| James Glennon | Assistant Camera |
| Thomas Laughridge | Camera Operator |
| Keith Mason | Key Grip |
| Julie Zale | Assistant Editor |
| Alex Tavoularis | Location Coordinator |
| Nancy Hopton | Script Supervisor |
| Mona Houghton | Administrative Assistant |
| Wayne Fitzgerald | Title Designer |
| Francis Ford Coppola | Writer |
