| Publisher | Title | # of Issues |
|---|---|---|
| ACG Comics | James O'Barr's Original Sins (1999) | 1 |
| Minotaur Comics | Obergeist: Ragnarok Highway | 6 |
| Image Comics/Top Cow Comics | Obergeist: The Empty Locket | 1 |
| DC Comics/Wildstorm Comics | Ocean (2004-2005) | 6 |
| Oni Press | Ojo | 5 |
| IDW Publishing | Olympus Heights | 1 |
| Oni Press | Oni Double Feature | 13 |
| Oni Press | Only the End of the World Again (2000) | 1 |
| DC Comics/Vertigo Comics | Otherworld (2005) | 6 |
| DC Comics/Vertigo Comics | Outlaw Nation (2000-2002) | 1 |
| Amaze Ink/Slave Labor Graphics | Outlook Grim (2003-2004) | 1 |
| Marvel Comics | Ozma of Oz (2010-2011) | 2 |
