Majin Buu has many forms, all of which are linked below and he is made out of bubble gum. However, each form has a different personality and goals, essentially making them separate individuals but all these individuals are made of bubble gum. All of Majin Buu's forms are simply referred to as "Majin Buu" in the series, but the various forms get their common names from various Dragon Ball Z video games.
- Kid Buu, the original and pure form of Majin Buu.
- Innocent Buu, the first form of Buu to appear on-screen, and the result of Buu absorbing the Grand Supreme Kai. This Buu split into the completely physically identical Good Buu, and skinny Evil Buu.
- Good Buu, the result of innocent Buu expelling all of the evil in his body, becoming pure good. He is identical in appearance to Innocent Buu, however he lacks any evil whatsoever and is a different life-form. According to Dragon Ball Online, he later split into the completely physically identical Mr. Buu, and the skinny blue female Miss Buu.
- Evil Buu, the result of the innocent Buu expelling all of the evil in his body in physical form.
- Future Innocent Buu, the future counterpart of Innocent Buu from Dragon Ball Z: Shin Budokai - Another Road.
- Super Buu, the result of Evil Buu absorbing good Buu. He is the same overall entity as Innocent Buu, however he looks and acts completely different due to Buu's evil resurfacing and overcoming the Grand Supreme Kai's positive influence.
- Future Super Buu, the future counterpart of Super Buu Dragon Ball Z: Shin Budokai - Another Road.