Snake: Colonel, I need you to describe my seiyuu here for me.
Colonel: You want to know about David Hayter, huh, Snake?
Snake: Huh? No, not him.
Colonel: Well, then Kiefer Sutherland?
Snake: No, Kiefer voices Big Boss. Not my English voice actor, Colonel, but my Japanese seiyuu.
Colonel: Oh, right. My mistake. Akio Ohtsuka, born November 24, 1959, is one of the most respected veterans in the seiyuu business. He's the son of another veteran seiyuu, Chikao Ohtsuka, making him an old son. Until a few years ago, he was also married to another seiyuu, Yoko Soumi, known for her Vamp, serious lady or Femme Fatale roles, like Karen Kasumi from X1999 the TV series and Atsuko from YuYu Hakusho.
Snake: So he's part of seiyuu royalty, eh? I wouldn't be surprised if his kids became seiyuu as well.
Colonel: Known for a deep, gruff voice that fits him into veteran-like roles, Akio often lands characters who are widely considered Badass, making him quite a fan favorite amongst older seiyuu. He'll gladly do humor roles as well.
Snake: Going from serious to humorous, eh? Wouldn't it be best to stick to one role?
Note: May also be spelt as "Ootsuka" instead in romaji. He also appears in live-action roles in TV, movies and video games from time to time.
- Dr. Seiichi Saeki in 428: Shibuya Scramble
- Alandus in Granblue Fantasy
- "All For One" in My Hero Academia
- "Ansem" and Terra-Xehanort in Kingdom Hearts
- Master Xehanort in Kingdom Hearts III
- Anavel Gato in Mobile Suit Gundam 0083: Stardust Memory, Super Robot Wars F, Super Robot Wars Alpha 1 and 2, Super Robot Wars Impact and Super Robot Wars Advance Portable
- Bana in Xenoblade Chronicles 2
- Batou in the Ghost in the Shell franchise
- Benkei in Genji
- Bernardo O'Reilly in the flight screening Japanese dub of The Magnificent Seven, taking over from his father, more or less.
- Dr. Black Jack in Black Jack
- The eponymous vampire hunter Blade
- Blitz T. "Lucky" Abrams in Blood Blockade Battlefront
- Bluebeard in Marchen, as well as the narration in some of Sound Horizon's concerts.
- Bobby in the Japanese dub of Animaniacs
- Boss in 12Riven
- Boy in Yarudora series vol.3: Sampaguita
- Ring Star Champ/Oushi Black in Uchu Sentai Kyuranger
- Daigo Kazama in Project Justice (replacing Kōichi Yamadera)
- Vice-Foreign Minister Darlian and the Narrator in Mobile Suit Gundam Wing
- Denzo Yamada (2nd voice) in Nintama Rantarou (replacing his father Chikao Ohtsuka, who sadly passed away during production)
- Die-Hardman in Death Stranding
- Dick Dastardly/Black Maou in the Japanese dub of Wacky Races (2017) (once again, taking the mantle from his father who voiced Dastardly in the original series Japanese dub as well as Dastardly and Muttley in Their Flying Machines)
- Dimple in Mob Psycho 100.
- Elmer Snell in Mobile Suit Gundam MS IGLOO 2: The Gravity Front
- Ernest Thompson Seton in Time Bokan 24
- Frank Castle/The Punisher in the Japanese dubs of The Punisher (1989) and Punisher: War Zone
- Judge Gabranth in Final Fantasy XII and Dissidia Final Fantasy
- Gaius van Baelsar in Final Fantasy XIV
- Garland (Garr) in Breath of Fire III: Drama Album
- Garon in Fire Emblem Fates
- First Lieutenant Garuru in Sgt. Frog
- Gio in Atelier Rorona and Meruru
- Go Karuma (Manfred von Karma) in the anime adaptation of Ace Attorney
- Gozo Aida in Agent Aika
- Gregorio Silva in Code Vein
- Gwendal von Voltaire in Kyo Kara Maoh!
- Hades in Saint Seiya
- Han Solo (Harrison Ford) in the Japanese dub of Star Wars
- Hazel Rainart in the Japanese dub of RWBY.
- Hawkins in the anime adaptation of The Secret Garden
- Director Higashio in Majin Bone
- Hyo Amano in The Last Blade
- Graves, the Outlaw in the Japanese dub of League of Legends
- Iron Will in the Japanese dub of My Little Pony: Friendship Is Magic
- Jeralt in Fire Emblem: Three Houses
- Jules Winfield (Samuel L. Jackson) in the Japanese dub of Pulp Fiction
- Jukai-Sensei in Dororo
- Kaite Madigan in Mobile Suit Gundam SEED Astray
- Kyoraku Shunsui in the Bleach franchise
- Laike in Lunar: Silver Star Story
- Leo Johnson (Eric DaRe) in the Japanese dub of Twin Peaks
- Mario Auditore in Assassin's Creed II
- Marshall D. Teach (better known as "Blackbeard") in One Piece
- His father Chikao Ohtsuka played Gol D. Roger.
- Mihai in the Dogs: Stray Dogs Howling in the Dark OVA
- Minamoto no Yoritomo and Unknown Soldier P1 in Namco × Capcom
- Moominpappa in Tanoshii Moomin Ikka
- Morrison in Devil May Cry: The Animated Series and Devil May Cry 5
- Mushiban in Yes! Pretty Cure 5 Go Go! The Movie: Happy Birthday in the Land of Sweets
- Orcus in Phantasy Star Nova
- Radi Yaeger in Valkyria Chronicles
- Regal Bryant in Tales of Symphonia
- Rider (Alexander the Great) in Fate/Zero and Fate/Grand Order
- Rin's grandfather and The Narrator in Laid-Back Camp
- Ryouma Hoshi in New Danganronpa V3
- Samurai Goroh in Super Smash Bros.
- Seiya Ogata in Sakura Wars 2: Thou Shalt Not Die and the Sakura Wars: The Radiant Gorgeous Blooming Cherry Blossoms OVA
- Seth in Street Fighter IV and Project X Zone
- Shingen Kishitani in Durarara!!
- Siam in Canaan
- The Skull Knight in Berserk: The Golden Age Arc, Berserk (2016), and Berserk and the Band of the Hawk.
- Solid Snake, Solidus Snake and Naked Snake/Venom Snake/Big Boss in Metal Gear.
- Souichi "Ironman" Nishimura in Baka and Test: Summon the Beasts
- Souther in Fist of the North Star (Movie version; succeeds Banjo Ginga, who is ironically Liquid Snake)
- His father Chikao Ohtsuka played Ryuuken and previously played Jagi in the 80s movie.
- Spider-Man: Noir in the Japanese dub of Spider-Man: Into the Spider-Verse.
- Uvogin and Mizaistom in Hunter × Hunter (2011)
- Tadakatsu Honda in the Samurai Warriors franchise
- Tetsuzo Nihei in Golden Kamuy
- Thorkell the Tall in Vinland Saga
- Wamuu in JoJo's Bizarre Adventure: Battle Tendency
- Windam in Magic Knight Rayearth
- Captain William Rush from Time Crisis 4
- Dub voice for: