Yu-Gi-Oh! Duel Monsters II: Dark duel Stories (遊戯王デュエルモンスターズＩＩ 闇界決闘記 Yugiō Dyuerumonsutāzu Ni Dākudyuerusutōrīzu) is a video game for the Game Boy Color, the second video game in the Yu-Gi-Oh! Duel Monsters series, following Yu-Gi-Oh! Duel Monsters and followed by Yu-Gi-Oh! Dark Duel Stories. It was developed and published by Konami and released on July 8, 1999 in Japan; it was never released internationally.

Duel Monsters II builds on the rules established in its predecessor, though the gameplay is still much simpler than the OCG. In addition to the 365 cards from Duel Monsters, it introduced 355 new cards, for a total of 720. Trap Cards and Ritual Cards were first included in it.