| One Many Nobody (2022) | 1,130 | 22 |
| One Military Camp (2023) | 9,309,453 | 1,787 |
| One Million People's Nobunaga's Ambition (2010) | 16,166 | 4 |
| One Million Worlds (2019) | 16 | 1 |
| One More Dungeon (2015) | 391,297 | 328 |
| One More Dungeon 2 (2022) | 314,345 | 241 |
| One More Gate : A Wakfu Legend (2022) | 468,384 | 416 |
| One More Island (2022) | 351,236 | 214 |
| One More Line (2014) | 399,178 | 98 |
| One More Shooter Game (2023) | 476 | 6 |
| One Must Fall: 2097 (1994) | 1,381,121 | 594 |
| One Must Fall: Battlegrounds (2003) | 82,672 | 23 |
| One Night at Flumpty's (2015) | 304,517,548 | 7,960 |
| One Night at Flumpty's 3 (2021) | 133,120,063 | 3,874 |
| One Night in Kawami (2024) | 38 | 1 |
| One Night Stand (2016) | 65,197,366 | 1,429 |
| One Night With Stalin (2022) | 13,648 | 29 |
| One Night You're Crazy (2017) | 0 | 0 |
| One Night ~Young Bride for One Night (2024) | 930 | 2 |
| One night, Hot springs (2018) | 276,941 | 241 |
| One Night: Burlesque (2023) | 18,643 | 28 |
| One on One: Dr. J vs. Larry Bird (1983) | 142,395 | 69 |
| One Person Story (2018) | 7,686 | 24 |
| One Piece (2005) | 2,228,558 | 1,844 |
| One Piece - Nanatsu Shima no Daihihou (2002) | 24,905 | 29 |
| One Piece Bounty Rush (2018) | 349,330,079 | 86,912 |
| One Piece Grand Battle! 3 (2003) | 998,773 | 456 |
| One Piece Mansion (2001) | 1,107,049 | 100 |
| One Piece Odyssey (2023) | 99,383,224 | 55,993 |
| One Piece Treasure Battle! (2002) | 345,316 | 206 |
| One Piece Treasure Cruise (2014) | 193,112,412 | 33,561 |
| One Piece Unlimited Cruise 1 Wii (2008) | 3,281 | 22 |
| One Piece Unlimited Cruise: Episode 2 (2009) | 3,934,975 | 466 |
| One Piece: Become the Pirate King! (2000) | 23,079 | 35 |
| One Piece: Burning Blood (2016) | 200,972,805 | 25,668 |
| One Piece: Chopper no Daibouken (2003) | 18,740 | 17 |
| One Piece: Dai Kaizoku Colosseum (2016) | 887,424 | 107 |
| One Piece: Doragon Doriimu! (2005) | 34,976 | 19 |
| One Piece: Gear Spirit (2007) | 2,333,912 | 162 |
| One Piece: Gigant Battle! 2 - New World (2011) | 1,124,958 | 492 |
| One Piece: Going Baseball - Kaizoku Yakyuu (2004) | 3,750,506 | 57 |
| One Piece: Grand Adventure (2006) | 3,981,970 | 2,837 |
| One Piece: Grand Battle Swan Colosseum (2002) | 232,552 | 127 |
| One Piece: Grand Battle! (2005) | 5,628,842 | 2,941 |
| One Piece: Grand Cruise (2018) | 2,230,983 | 164 |
| One Piece: Great Pirate Colosseum (2016) | 410,463 | 156 |
| One Piece: Maboroshi no Grand Line Boukenki (2002) | 38,756 | 93 |
| One Piece: Niji no Shima Densetsu (2001) | 4,331 | 11 |
| One Piece: Ocean's Dream (2003) | 32,991 | 29 |
| One Piece: Pirate Warriors (2012) | 99,367,813 | 22,032 |
| One Piece: Pirate Warriors 2 (2013) | 54,810,717 | 8,280 |
| One Piece: Pirate Warriors 3 (2015) | 163,432,159 | 37,043 |
| One Piece: Pirate Warriors 4 (2020) | 531,443,861 | 106,885 |
| One Piece: Pirates' Carnival (2005) | 550,431 | 383 |
| One Piece: Romance Dawn (2012) | 4,835,055 | 2,411 |
| One Piece: Round the Land (2004) | 645,630 | 571 |
| One Piece: Super Grand Battle! X (2014) | 2,772,655 | 234 |
| One Piece: Thousand Storm (2016) | 18,713,255 | 6,105 |
| One Piece: Treasure Wars (2002) | 17,271 | 21 |
| One Piece: Treasure Wars 2 - Welcome to Buggyland (2002) | 3,540 | 10 |
| One Piece: Unlimited Adventure (2007) | 8,660,568 | 1,393 |
| One Piece: Unlimited Cruise (2008) | 7,428,000 | 1,910 |
| One Piece: Unlimited Cruise SP (2011) | 2,478,915 | 235 |
| One Piece: Unlimited World Red (2013) | 44,100,142 | 8,602 |
| One Piece: World Seeker (2019) | 92,824,767 | 21,044 |
| One Piece: Yume no Lufy Kaizokudan Tanjou (2001) | 22,910 | 80 |
| One Punch Man: A Hero Nobody Knows (2020) | 113,197,562 | 10,981 |
| One Room Dungeon (2025) | 27,654 | 34 |
| One S'More (2024) | 310 | 10 |
| One Shell Straight to Hell (2021) | 625,006 | 92 |
| One Socket (2024) | 71,443 | 20 |
| One Step After Fall (2022) | 72,544 | 198 |
| One Step From Eden (2020) | 6,109,832 | 5,409 |
| One Strike (2017) | 599,678 | 256 |
| One Tank Army (2023) | 39 | 1 |
