| Jon Stewart | ... | Himself - Host |
| rest of cast listed alphabetically: |
| Amy Adams | ... | Herself - Nominee: Best Actress in a Supporting Role |
| Moustapha Akkad | ... | Himself, in memorial sequence (archive footage) |
| Jessica Alba | ... | Herself - Co-Presenter: Best Sound Mixing |
| Eddie Albert | ... | (archive footage) |
| Muhammad Ali | ... | Himself (archive footage) |
| Robert Altman | ... | Himself - Honorary Award Recipient |
| Jennifer Aniston | ... | Herself - Presenter: Best Costume Design |
| Colleen Atwood | ... | Herself - Winner: Best Costume Design |
| Lauren Bacall | ... | Herself - Presenter |
| Eric Bana | ... | Himself - Presenter: Best Sound Mixing |
| Anne Bancroft | ... | (archive footage) |
 | Paul Beauregard | ... | Himself - Winner: Best Original Song |
| Dion Beebe | ... | Himself - Winner: Best Cinematography |
| Barbara Bel Geddes | ... | (archive footage) |
| Howard Berger | ... | Himself - Winner: Best Makeup |
| Nicole Berger | ... | Dancer |
| John Box | ... | Himself, in memorial sequence (archive footage) |
| Steve Box | ... | Himself - Winner: Best Animated Feature |
| Christopher Boyes | ... | Himself - Winner: Best Sound Mixing |
| Zach Braff | ... | Chicken Little - Presenter: Best Animated Short Film (voice) |
| Sandra Bullock | ... | Herself - Presenter: Best Art Direction |
| Tim Burton | ... | Himself - Nominee: Best Animated Feature Film |
| Jordi Caballero | ... | Dancer |
| John Canemaker | ... | Himself - Winner: Best Short Film - Animated |
| Kate Capshaw | ... | Herself - Audience Member |
| Steve Carell | ... | Himself- Presenter: Best Makeup |
| George Clooney | ... | Himself - Winner: Best Actor in a Supporting Role / Nominee: Best Director and Best Original Screenplay / Presenter: In Memoriam |
| Cedric Coleman | ... | Himself - Winner: Best Original Song |
| Russell Crowe | ... | Himself - Presenter: Biographical Film Montage |
| Joan Cusack | ... | Abby Mallard - Co-presenter: Best Animated Short Film (voice) |
| Yves Darondeau | ... | Himself - Winner: Best Documentary Feature |
| Sandra Dee | ... | Memorial sequence (archive footage) |
| Judi Dench | ... | Herself - Nominee: Best Actress in a Leading Role |
| Matt Dillon | ... | Himself - Nominee: Best Actor in a Supporting Role |
| Will Ferrell | ... | Himself - Co-Presenter: Best Makeup |
| John Fiedler | ... | Memorial sequence (archive footage) |
| Jamie Foxx | ... | Himself - Presenter: Best Actress in a Leading Role |
| Anthony Franciosa | ... | Memorial sequence (archive footage) |
| Morgan Freeman | ... | Himself - Presenter: Best Supporting Actor |
| Mohandas K. Gandhi | ... | Himself (archive footage) (as Mahatma Gandhi) |
| Sidney Ganis | ... | Himself - Academy President (as Sid Ganis) |
| Jennifer Garner | ... | Presenter - Best Sound Editing |
| Lou Gehrig | ... | Himself (archive footage) |
| Paul Giamatti | ... | Himself - Nominee: Best Actor in a Supporting Role |
| Guy Green | ... | Himself - memorial sequence (archive footage) |
| Jake Gyllenhaal | ... | Himself - Nominee / Presenter |
| Paul Haggis | ... | Himself - Winner: Best Picture / Screenplay |
| Tom Hanks | ... | Himself |
| Salma Hayek | ... | Herself - Presenter: Best Original Score |
| Kasie Head | ... | Trophy Presenter |
| Michael Hedges | ... | Himself - Winner: Best Sound Mixing |
| Debra Hill | ... | Herself, in memorial sequence (archive footage) |
| Joel Hirschhorn | ... | Himself, in memorial sequence (archive footage) |
| Dustin Hoffman | ... | Himself - Presenter: Best Adapted Screenplay |
| Philip Seymour Hoffman | ... | Himself - Winner: Best Actor in a Leading Role |
| Gavin Hood | ... | Himself - Winner: Best Foreign Film |
| Mike Hopkins | ... | Himself - Winner: Best Sound Editing |
| Jordan Houston | ... | Himself - Winner: Best Original Song |
| Terrence Howard | ... | Himself - Presenter: Best Documentary Short & Nominee: Best Actor in a Leading Role |
| Felicity Huffman | ... | Herself - Nominee: Best Actress in a Leading Role |
| William Hurt | ... | Himself - Nominee: Best Actor in a Supporting Role |
| Alberto Iglesias | ... | Himself - Nominee: Best Original Score |
| Samuel L. Jackson | ... | Himself - Presenter |
| Luc Jacquet | ... | Himself - Winner: Best Documentary Feature |
| Tom Kane | ... | Announcer |
| Catherine Keener | ... | Herself - Nominee: Best Actress in a Supporting Role |
| Kathleen Kennedy | ... | Herself - Nominee: Best Picture |
| Nicole Kidman | ... | Herself - Presenter: Best Supporting Actor |
| Keira Knightley | ... | Herself - Nominee: Best Actress in a Leading Role |
| Robert Knudson | ... | Himself, in memorial sequence (archive footage) |
| Tami Lane | ... | Herself - Winner: Best Makeup |
| Queen Latifah | ... | Herself - Presenter: Best Original Song |
| Heath Ledger | ... | Himself - Nominee: Best Actor in a Leading Role |
| Ang Lee | ... | Himself - Winner: Best Director |
| Ernest Lehman | ... | Himself, in memorial sequence (archive footage) |
| Joe Letteri | ... | Himself - Winner: Best Visual Effects |
| Stu Linder | ... | Himself, in memorial sequence (archive footage) |
| Jennifer Lopez | ... | Herself - Presenter: Best Sound Editing |
| Ludacris | ... | Himself - Presenter: Song Performance 'It's Hard Out Here for a Pimp' (as Chris 'Ludacris' Bridges) |
| William H. Macy | ... | Himself |
| Corinne Marrinan | ... | Himself - Winner: Best Short Film - Documentary |
| Rachel McAdams | ... | Herself - Presenter: Scientific & Technical Achievement Awards |
| James McAvoy | ... | Himself / Mr. Tumnus, the Faun (archive footage) |
| Martin McDonagh | ... | Himself - Winner: Best Short Film, Live Action |
| Frances McDormand | ... | Herself - Nominee: Best Actress in a Supporting Role |
| Larry McMurtry | ... | Himself - Winner: Best Adapted Screenplay |
| Ismail Merchant | ... | Himself, in memorial sequence (archive footage) |
| Bennett Miller | ... | Himself - Nominee: Best Director |
| John Mills | ... | (archive footage) |
| Terry Moore | ... | Herself - Audience Member |
| Robert Moresco | ... | Himself - Winner: Best Original Screenplay (as Bobby Moresco) |
| Pat Morita | ... | (archive footage) (as Noriyuki 'Pat' Morita) |
| John Myhre | ... | Himself - Winner: Best Art Direction |
| John Nash | ... | Himself (archive footage) (as John Forbes Nash) |
| Robert F. Newmyer | ... | Himself, in memorial sequence (archive footage) |
| Fayard Nicholas | ... | (archive footage) |
| Jack Nicholson | ... | Himself - Presenter: Best Picture |
| Dan O'Herlihy | ... | (archive footage) |
| Diana Ossana | ... | Herself - Winner: Best Adapted Screenplay & Nominee: Best Picture |
| Nick Park | ... | Himself - Winner: Best Animated Feature |
| Dolly Parton | ... | Herself - Nominee: Best Original Song / Performer |
| George S. Patton | ... | Himself (archive footage) |
| Hammond Peek | ... | Himself - Winner: Best Sound Mixing |
| Chris Penn | ... | (archive footage) |
| Itzhak Perlman | ... | Himself - Performer |
| Brock Peters | ... | (archive footage) |
| Marisa Petroro | ... | Trophy Presenter |
| Joaquin Phoenix | ... | Himself - Nominee: Best Actor in a Leading Role |
| Rodrigo Prieto | ... | Himself - Nominee: Best Cinematography |
| Richard Pryor | ... | (archive footage) |
| Susan Raab Simonson | ... | Herself - Guest |
| Joe Ranft | ... | Himself, in memorial sequence (archive footage) |
| Gretchen Rau | ... | Herself - Winner: Best Art Direction |
| Keanu Reeves | ... | Himself - Co-Presenter: Best Art Direction |
| Christian Rivers | ... | Himself - Winner: Best Visual Effects |
| Mickey Rooney | ... | Himself - Audience Member |
| Jane Russell | ... | Herself - Audience Member |
| Gustavo Santaolalla | ... | Himself - Winner: Best Original Score |
| Vincent Schiavelli | ... | Memorial sequence (archive footage) |
| Robert J. Schiffer | ... | Himself, in memorial sequence (archive footage) |
| Cathy Schulman | ... | Herself - Winner: Best Picture |
| Michael Semanick | ... | Himself - Winner: Best Sound Mixing |
| Moira Shearer | ... | Memorial sequence (archive footage) |
| Dean Silvers | ... | Himself |
| Forrest Silvers | ... | Himself |
| Simone Simon | ... | Memorial sequence (archive footage) |
| Eric Simonson | ... | Himself - Winner: Best Short Film - Documentary |
| Will Smith | ... | Himself - Presenter: Best Foreign Film |
| Steven Spielberg | ... | Himself - Nominee: Best Picture & Best Director |
| Kevin Alexander Stea | ... | Dancer - It's Hard Out Here For A Pimp |
| Peggy Stern | ... | Herself - Winner: Best Short Film - Animated |
| Ben Stiller | ... | Himself - Presenter: Best Visual Effects |
| David Strathairn | ... | Himself - Nominee: Best Actor in a Leading Role |
| Meryl Streep | ... | Herself - Co-presenter: Honorary Award to Robert Altman |
| Hilary Swank | ... | Herself - Presenter: Best Actor |
| Richard Taylor | ... | Himself - Winner: Best Visual Effects |
| Charlize Theron | ... | Herself - Nominee: Best Actress in a Leading Role & Presenter: Best Documentary Feature |
| Three 6 Mafia | ... | Themselves - Performers ("It's Hard Out Here for a Pimp") |
| Uma Thurman | ... | Herself - Presenter |
| Lily Tomlin | ... | Herself - Co-presenter: Honorary Award to Robert Altman |
| John Travolta | ... | Himself - Presenter: Best Cinematography |
| Casey Tutton | ... | Steve Martin's Daughter in Jon Stewart's Opening Film |
| Ryan Tutton | ... | Steve Martin's Son in Jon Stewart's Opening Film |
| Ethan Van der Ryn | ... | Himself - Winner: Best Sound Editing |
| Brian Van't Hul | ... | Himself - Winner: Best Visual Effects |
| Nacho Vigalondo | ... | Himself - Audience Member |
| Naomi Watts | ... | Herself - Presenter |
| Rachel Weisz | ... | Herself - Winner: Best Actress in a Supporting Role |
| Onna White | ... | Herself, in memorial sequence (archive footage) |
| John Williams | ... | Himself - Nominee: Best Original Score |
| Michelle Williams | ... | Herself - Nominee: Best Actress in a Supporting Role |
| Luke Wilson | ... | Himself - Co-Presenter: Best Live Action Short |
| Owen Wilson | ... | Himself - Co-Presenter: Best Live Action Short |
| Rita Wilson | ... | Herself - Audience Member |
| Hughes Winborne | ... | Himself - Winner: Best Editing |
| Shelley Winters | ... | (archive footage) |
| Robert Wise | ... | Himself, in memorial sequence (archive footage) |
| Reese Witherspoon | ... | Herself - Winner: Best Actress in a Leading Role & presenter: Best Animated Feature |
| Edward D. Wood Jr. | ... | Himself (archive footage) (as Ed Wood) |
| Teresa Wright | ... | Memorial sequence (archive footage) |
| Kathleen York | ... | Herself - Nominee: Best Original Song & Performer (as Kathleen 'Bird' York) |
| Hawk Younkins | ... | Himself |
| Danielle Yu | ... | Trophy Presenter |
| Ziyi Zhang | ... | Herself - Presenter: Best Film Editing |
| Javier Bardem | ... | Ramón Sampedro (archive footage) (uncredited) |
| Halle Berry | ... | Herself, in opening segment (uncredited) |
| Stephen Colbert | ... | Narrator of Attack Ads (voice) (uncredited) |
| Billy Crystal | ... | Himself, in opening segment [pre-recorded] (uncredited) |
| Mel Gibson | ... | Himself, in opening segment [pre-recorded] (uncredited) |
| Whoopi Goldberg | ... | Herself, in opening segment (uncredited) |
| Russ Leatherman | ... | Mr. Moviefone (uncredited) |
| David Letterman | ... | Himself, in opening segment [pre-recorded] (uncredited) |
| Steve Martin | ... | Himself, in opening segment (uncredited) |
| Tim Byron Owen | ... | Saxaphonist (uncredited) |
| Chris Rock | ... | Himself, in opening segment [pre-recorded] (uncredited) |
| Big Spence | ... | Himself (uncredited) |
company.