Dragon Ball Z: Kyoushuu! Saiyajin focuses on the battles of characters from the Dragon Ball universe, particularly the Saiyan race, which is one of the key species in the story. The game's storyline centers around the events during the time when the Saiyans (such as Vegeta and Nappa) invade Earth and battle Goku and the Z Fighters. This occurs when Raditz, Vegeta, and Nappa arrive on Earth to destroy humanity and gather energy, with the content taking place during significant events in the Dragon Ball Z series.