Short, a former "Saturday Night Live" player who has appeared in the films "Three Amigos" and "Innerspace," is to voice the role of the Jester.
"We are delighted and excited to work with Mr. Short. He is perfect for the role of the Jester, which requires his nimble abilities at comedy, impressions, music and spontaneity," Executive Producer Neil Kaufman said in a statement.
Belushi, best known for his TV sit-com "According to Jim," is to play the role of the Lion.
"I've been a huge fan of Jim's for many years and am pleased and excited to be working with a fellow Chicagoan on this project," said Alpine's Chief Executive Officer Ryan J. Carroll.
"Dorothy of Oz" is the first in a planned series of animated feature films by Alpine Pictures, in association with Box Office Productions III, based on the work of children's writer Roger S. Baum.
Baum's work continues the legacy begun by his great-grandfather, L. Frank Baum, author of "The Wonderful Wizard of Oz."