Starting Characters
Baby Mario, Baby Peach, Toad, Koopa, Mario, Luigi, Yoshi, Peach, Wario, Waluigi, Donkey Kong, Bowser
Unlockable Characters
- King Boo – Win 50cc Star Cup
- Diddy Kong – Win all 50cc Cups
- Baby Daisy – Attain at least 1 Star Rank for all 50cc Wii Grand Prix Cups
- Mii (Outfit A) – Win 100cc Special Cup
- Mii (Outfit B) – Unlock 32 Expert Staff Ghost Data in Time Trials
- Mii (Outfit C) - Get 15,000 points in VS mode – *unconfirmed & probably fake
- Dry Bones – Win 100cc Leaf Cup
- Bowser Jr. – Attain at least 1 Star Rank for all 100cc Retro Grand Prix Cups
- Daisy – Win 150cc Special Cup
- Dry Bowser – Attain at least 1 Star Rank for all 150cc Wii Grand Prix Cups
- Funky Kong – Unlock 4 Expert Staff Ghost Data in Time Trials
- Baby Luigi – Unlock 8 Expert Staff Ghost Data in Time Trials
- Birdo – Play Time Trials on 16 different courses/Get 250 wins online
- Toadette – Play Time Trials on all 32 different courses
- Rosalina - With a Super Mario Galaxy save, win a series of Grand Prix cups/Without Galaxy save, Attain at least 1 Star Rank for all Mirror Grand Prix Cup
Unlockable Karts
- Cheep Charger (small kart) – Attain at least 1 Star Rank for all 50cc Retro Grand Prix Cups
- Blue Falcon (small kart) – Win Mirror Lightning Cup
- Rally Romper (small kart) – Unlock 1 Expert Staff Ghost Data in Time Trials
- Turbo Blooper (medium kart) – Win 50cc Leaf Cup
- Royal Racer (medium kart) – Win 150cc Leaf Cup
- B-Dasher (medium kart) – Unlock 24 Expert Staff Ghost data
- Piranha Prowler (large kart) – Win 50cc Special Cup
- Dragonetti (large kart) – Win 150cc Lightning Cup
- Aero Glider (large kart) – Win all 150cc Retro Grand Prix Cups with 1 star or better
Unlockable Bikes
- Quacker (small bike) – Win 150cc Star Cup
- Bubble Bike (small bike) – Win Mirror Leaf Cup
- Magikruiser (small bike) – Play Time Trials on 8 different courses
- Rapide (medium bike) – Win 100cc Lightning Cup
- Nitrocycle (medium bike) – Attain at least 1 Star Rank for all 100cc Wii Grand Prix Cups
- Dolphin Dasher (medium bike) – Win Mirror Star Cup
- Twinkle Star (large bike) – Win 100cc Star Cup
- Phantom (large bike) – Win Mirror Special Cup
- Torpedo (large bike) – Unlock 12 Expert Staff Ghost Data in Time Trials
Misc Unlockables
- Picture option to send to Wii Message Board – Complete all 8 Cups in a class
- Karts & Bikes (50cc) – Earn trophies in all 50cc Grand Prix Cups
- Karts & Bikes (100cc) – Earn trophies in all 100cc Grand Prix Cups
- Mirror Class – Win all 150cc Cups
- Alternate Title Screen – Win all Cups