O
| Host | Country | Game show(s) hosted |
|---|---|---|
| Richard O'Brien | United Kingdom | The Crystal Maze (1990–93) |
| Kevin O'Connell | United States | Go (1983–84) |
| Brian O'Connor | United States | Rumor Has It (1993) |
| Des O'Connor | United Kingdom | Countdown (2007–08), Take Your Pick |
| John O'Hurley | United States | To Tell the Truth (2000–02), Family Feud (2006–09) |
| Andrew O'Keefe | Australia | Deal or No Deal (2004–present) |
| Dermot O'Leary | United Kingdom | 1 vs. 100 (2007–present) |
| Mike O'Malley | United States | Get the Picture (1991–93), Guts/Global Guts/Nickelodeon GUTS (1992–95) |
| James O'Neill | Australia | Hot Streak |
| Ken Ober | United States | Remote Control (1987–91), Make Me Laugh (1997), Smush (2001) |
| Steve Oemcke | Australia | Wheel of Fortune |
| Fergie Olver | Canada | Just Like Mom (1980–87) |
| Donny Osmond | United States | Pyramid (2002–04) |
| Gary Owens | United States | Letters to Laugh-In (1969), The Gong Show (1976–77) |
Read more about this topic: List Of Game Show Hosts