The 17-year-old wildlife conservationist will be joining the show this fall. Irwin is the daughter of Steve Irwin, better known as "The Crocodile Hunter," who died in 2006. She inherited her dad's passion for wildlife and the entertainment industry, she writes on the website Australia Zoo.
"This is completely different to anything I have ever done in my life," she said on Good Morning America Monday. "I'm just this girl from Australia who's used to crocs."
Irwin just got back from working on crocodile research. She said she has no experience with ballroom dancing, so she's more nervous about the show's judges than she was doing her wildlife research.
ABC has also announced many of the professional dancers that will join the show this season, and fans will recognize some familiar faces.
PHOTOS: Dancing with the Stars season 21 professional dancers
The celebrity cast announcements will continue all week long.
Dancing with the Stars season 21 will premiere Sept. 14 on ABC at 8 p.m. ET | 7 p.m. CT.