- Off/On by FV
- Off the Books / Just to Get a Rep (MF Doom Special Blend) (Ft. Big Pun, Cuban Link, Juju (Beatnuts) & Psycho Les) prod. by Metal Fingers
- Oh, Deer (Beddar Daze) by Joey Bada$$
- Oil by MC Paul Barman
- Old School Rules by DANGERDOOM (Ft. Talib Kweli) prod. by Danger Mouse
- OM by NehruvianDOOM prod. by Metal Fingers
- One Beer prod. by Madlib
- One Smart Nigger by King Geedorah prod. by Metal Fingers
- Open Mic Nite, Pt. 1 by Viktor Vaughn (Ft. Brother Sambuka, Dr. Moreau, Lord Sear & Louis Logic) prod. by King Honey
- Open Mic Nite, Pt. 2 by Viktor Vaughn (Ft. Creature & Lord Sear) prod. by King Honey & Mr. Ten
- Operation: Greenbacks (Ft. Megalon)
- Operation Lifesaver AKA Mint Test by Madvillain prod. by Madlib
- Outro - Fatman Scoop (Special Herbs + Spices Vol. 1) by MF DOOM & MF Grimm (Ft. Fatman Scoop) prod. by Metal Fingers
- Overture by Viktor Vaughn prod. by Metal Fingers
- Owl by The Child Of Lov prod. by The Child Of Lov
- Papermill by Madvillain prod. by Madlib
- Patchouly Leaves prod. by Metal Fingers
- Pause Tape by JJ DOOM prod. by Jneiro Jarel
- PBS by Masta Ace (Ft. Masta Ace)
- Peachfuzz by KMD prod. by KMD