"I am so excited to be able to sing the national anthem at this year's Indy 500," said Hough in a Tuesday statement. "I've never been to the race, and it will give me a chance to cheer on my friend and dancing partner Helio."
Hough and Castroneves -- a two-time, back-to-back Indianapolis 500 champion who won the IndyCar race in 2001 and 2002 -- claimed the show's fifth-season mirror ball trophy last November.
"Julianne danced into the hearts of Indianapolis 500 fans everywhere through her performances with Helio during Dancing with the Stars," said Indianapolis Motor Speedway president and COO Joie Chitwood in a Tuesday statement.
"We're happy to welcome her to the Speedway and eager for her to show her impressive musical talent to the world before The Greatest Spectacle in Racing."