Mii’s are a secret character in Mario Kart Wii, other than racing in the game they can be seen in the background of different courses. To unlock them you need to unlock one of their outfits, to unlock Outfit A (It’s in the mii’s favorite color) you have to win 100cc of the Special cup or do 1650 races. To unlock Outfit B (If female receives a princess peach like dress, if male they receive mario brothers overalls) they must unlock expert ghost data win 5000 online races or ghost races or 5100 races/battles. The Mii can be small, medium or large depending on their height and weight, by changing your Mii’s height you can change what karts it’s able to drive.
Character Driving Bonus
| Name | Speed | Weight | Accele-ration | Handling | Drift | Off-Road | Mini-Turbo |
| Small | 3 | 3 | 0 | 0 | 3 | 0 | 3 |
| Medium | 3 | 3 | 0 | 0 | 0 | 3 | 3 |
| Large | 3 | 0 | 3 | 3 | 3 | 0 | 3 |
