Clooney, a four-time SAG Award best actor winner, was nominated for his performance in Up in the Air.
Baldwin, who will co-host the Oscars in March with Steve Martin, got a SAG Award nod again this year for the NBC hit show 30 Rock. Streep is up for leading actress for her role in Julie & Julia.
Sandra Bullock, who is nominated for leading actress for The Blind Side, will present the Life Achievement Award to Betty White, her costar in The Proposal.
Other presenters announced Thursday are Stanley Tucci, Anna Paquin, Chris O'Donnell, Jane Lynch and Michelle Monaghan.
Watch the SAG Awards on Jan. 23, live on TNT and TBS – and catch up on all the news and style from the show on PEOPLE.com!