|
|
| Oblivious | Goons and Masters | Doom | |
| Oceans Of Sadness | Mirror Palace | Prog Metal | |
| Octavia Sperati | Winter Enclosure | Gothic | |
| October Equus | October Equus | Prog | |
| Odessa | The Final Day | Prog | |
| Odin's Court | Deathanity | Prog Metal | |
| Odra Reg | God's Garden | Prog | |
| Odyssice | Impression | Prog | |
| Of The Wand and the Moon | Emptiness, Emptiness, Emptiness | Gothic | |
| Ogogo + Linden | Ogogo + Linden | Avantgarde | |
| Ogogo | Redux | Avantgarde | |
| Ogogo | Lunar Surphase | Avantgarde | |
| Ohgr | Devils In My Details | Electronic | |
| Ohm | Ohm | Fusion | |
| Ohm | Live on PKFK 90.7 FM | Fusion | |
| O'Hora Tony | Escape Into the Sun | Hard Rock | |
| Okumoto Ryo | Coming Through | Prog | |
| Old Dead Tree | The Nameless Disease | Gothic Metal | |
| Oliver Wakeman Band | Coming to Town | Pomp | |
| Olivieri Luca | La Quarta Dimensione | World Ambient | |
| Olivieri Raffaele | Improvvisamente la Luna | new | Jazz |
| Olson Mark | The Salvation Blues | Roots Rock | |
| Omasphère | Prélude | World Music | |
| Omega | The Prophet | Prog Metal | |
| Omega Lithium | Dreams in Formaline | Gothic Metal | |
| Omni | El Vals de los Duendes | Prog | |
| Oniric | Suggestioni | Gothic | |
| Onze H30 | Onze H30 | Rock | |
| Oophoi & Louisa John Kroll | I Hear the Water Dreming | Electronic | |
| Open Up | Open Up | AOR | |
| Opera Noire | Bad Intent | Gothic | |
| Opposition Of One | I Try to Understand This | Metal Core | |
| Optimystical | Optimystical | AOR | |
| Opus Est | Opus I | Prog | |
| Orchestre Celesti | Compi la Tua Magia | new | Prog |
| Orchestre Celesti | Black and Red | new | Prog |
| Oresund Space Collective | Oresund Space Collective | Space Rock | |
| Oresund Space Collective | It's All About Delay | Space Rock | |
| Oresund Space Collective | The Black Tomato | Space Rock | |
| Oresund Space Collective | Good Planets Are Hard To Find | Space Rock | |
| Orford Martin | The Old Road | Rock | |
| Orme, Le | Live in Pennsylvania | Prog | |
| Orne | The Conjuration By the Fire | Dark Rock | |
| Orplid | Greifenherz | Neo Folk | |
| Osada Vida | Three Seats Behind a Triangle | Prog | |
| Osada Vida | The Body Parts Party | Prog | |
| Osada Vida | Uninvited Dreams | Prog | |
| Osi | Free | Prog Metal | |
| Osi | Blood | Prog Metal | |
| Osiris | Beyond Control | Prog | |
| Osiris | Visions From the Past | Prog | |
| Ossimoro | Corvi Nel Cielo Spento | Stoner | |
| Other, the | We Are Who We Eat | Horror Punk | |
| Other, the | New Blood | new | Horror Punk |
| OTR | Mamonama | Hard Rock | |
| O-U | O-U | Prog | |
| Outer Limits | Stromatolite | Prog | |
| Outgunned | Vol.I: Answering the Censeless Need | Prog Metal | |
| Outopsya | Sum | Prog Metal | |
| Over Jazz Duo | Beautiful Love | Jazz | |
| Over The Edge | Over The Edge | AOR | |
| Overfaith | Our Regretless Awakening | Heavy Metal | |
| Overhead | Metaepitome | Prog | |
| Overhead | And We're Not Here After All | Prog | |
| Overunit Machine | Antropophobia | Crossover | |
| Owens Tim Ripper | Play My Game | Heavy Metal | |
| Oz Noy | Ha! | Fusion | |
| Ozark Mountain Daredevils | Our Most Dangerous Stunts | Country | |
| Ozric Tentacles | Spirals in Hyperspace | Prog | |
| Ozric Tentacles | The Floor's Too Far Away | Prog |
