| Player | Pos | Team |
|---|---|---|
| Aidan O'Connell | QB | Las Vegas Raiders |
| Patrick O'Connell | LB | Seattle Seahawks |
| Brian O'Neill | OT | Minnesota Vikings |
| Eric O'Neill | DE | Detroit Lions |
| Connor O'Toole | LB | Seattle Seahawks |
| Namdi Obiazor | LB | New England Patriots |
| Jimto Obidegwu | OT | Jacksonville Jaguars |
| Adedayo Odeleye | DT | Dallas Cowboys |
| Dayo Odeyingbo | DE | Chicago Bears |
| Osa Odighizuwa | DT | San Francisco 49ers |
| George Odum | S | Houston Texans |
| Rome Odunze | WR | Chicago Bears |
| Emmanuel Ogbah | DE | Kansas City Chiefs |
| Amen Ogbongbemiga | LB | Detroit Lions |
| Otito Ogbonnia | DT | Dallas Cowboys |
| Drew Ogletree | TE | Indianapolis Colts |
| Dare Ogunbowale | RB | Houston Texans |
| David Ojabo | DE | New Orleans Saints |
| Moro Ojomo | DT | Philadelphia Eagles |
| John Ojukwu | OT | Philadelphia Eagles |
| Azeez Ojulari | LB | Las Vegas Raiders |
| BJ Ojulari | LB | Jacksonville Jaguars |
| Ty Okada | S | Seattle Seahawks |
| Bobby Okereke | LB | Carolina Panthers |
| Chig Okonkwo | TE | Washington Commanders |
| Chukwuma Okorafor | OT | New York Jets |
| Ogbo Okoronkwo | LB | San Francisco 49ers |
| CJ Okoye | DT | New York Giants |
| Sam Okuayinonu | DT | San Francisco 49ers |
| Kitan Oladapo | S | Green Bay Packers |
| Oluwafemi Oladejo | DE | Tennessee Titans |
| David Olajiga | DT | Baltimore Ravens |
| Chris Olave | WR | New Orleans Saints |
| Bryce Oliver | WR | Houston Texans |
| Collin Oliver | DE | Green Bay Packers |
| Ed Oliver | DT | Buffalo Bills |
| Isaiah Oliver | S | Tennessee Titans |
| Josh Oliver | TE | Minnesota Vikings |
| Gunner Olszewski | WR | New York Giants |
| Segun Olubi | LB | Las Vegas Raiders |
| Foyesade Oluokun | LB | Jacksonville Jaguars |
| Olu Oluwatimi | C | Seattle Seahawks |
| Charles Omenihu | DE | Washington Commanders |
| Ethan Onianwa | OT | Atlanta Falcons |
| Mike Onwenu | G | New England Patriots |
| Levi Onwuzurike | DE | Detroit Lions |
| Tyler Onyedim | DT | Denver Broncos |
| David Onyemata | DT | New York Jets |
| Domonique Orange | DT | Minnesota Vikings |
| Ruke Orhorhoro | DT | Jacksonville Jaguars |
| Anfernee Orji | LB | Philadelphia Eagles |
| Gavin Ortega | OT | Denver Broncos |
| Amani Oruwariye | CB | Baltimore Ravens |
| Matt Orzech | LS | Green Bay Packers |
| K.J. Osborn | WR | Tennessee Titans |
| Joseph Ossai | DE | New York Jets |
| K.C. Ossai | LB | Houston Texans |
| Esezi Otomewo | DT | Pittsburgh Steelers |
| Jaydn Ott | RB | Kansas City Chiefs |
| Tyler Ott | LS | Washington Commanders |
| Cade Otton | TE | Tampa Bay Buccaneers |
| Robbie Ouzts | FB | Seattle Seahawks |
| DeMarvion Overshown | LB | Dallas Cowboys |
| LT Overton | DT | Dallas Cowboys |
| Odafe Oweh | LB | Washington Commanders |
| Coleman Owen | WR | Green Bay Packers |
| Jonathan Owens | S | Indianapolis Colts |
| Tyler Owens | S | Washington Commanders |
| Jeremiah Owusu-Koramoah | LB | Cleveland Browns |