Authors: O
| Author (number of quotes) | Description |
| Oa | |
| Oates, Joyce Carol (2) | |
| Od | |
| Odell, Tom (1) | English-born composer and singer |
| Og | |
| Ogilvy, David (2) | |
| Ol | |
| Oldman, Gary (2) | English actor, author, filmdirector, and producer |
| Oliver, Lauren (3) | American author |
| Oliver, Mary (1) | |
| Olsen, Elizabeth (3) | American actress |
| Op | |
| Oppenheim, James (1) | American poet, author |
| Or | |
| Orben, Robert (4) | American author and magician |
| Orwell, George (17) | English author, criticist, journalist |
| Os | |
| Osbourne, Ozzy (4) | pen name of John Michael Osbourne, English singer |
| Osho (5) | Indian guru and spiritual teacher |
| Osler, William (1) | Canadian physician |
| Ot | |
| Ottolenghi, Yotam (1) | Israeli-British chef, restaurant owner, and food writer |
| Ov | |
| Ovid (1) | |
| Ow | |
| Owen, Clive (1) | English actor |
| Owens, Jesse (1) | American athlete |
| O`Brien, Dylan (1) | American actor |
| O`Rourke, Patrick Jake (1) | |