Frank may refer to:
- Incidental 42 - A red-orange fish with a blue shirt.
- Incidental 155 - A lifeguard at Goo Lagoon.
- Incidental 24 - A big brown fish with muscles.
- Incidental 105 - A brown fish with a red shirt.
- Frank (store owner) - Owner of the Palace of Pranks.
- Frank the guard - A cop.
- Frank the whale - A whale in "You Don't Know Sponge."
- Frank (Neptune's advisor) - One of King Neptune's three advisors.