Clooney, who plays a lonely travelling businessman, is nominated for Outstanding Performance by a Male Actor in a Leading Role, while his female co-stars Vera Farmiga and Anna Kendrick will go up against each other for the Outstanding Performance by a Female Actor in a Supporting Role prize.
Up In The Air ties with director Quentin Tarantino's Inglorious Basterds and Precious: Based On The Novel Push By Sapphire with a total of three nominations.
Clooney will fight it out for the lead actor accolade with Morgan Freeman (Invictus), Jeff Bridges (Crazy Heart), Colin Firth (A Single Man) and Jeremy Renner (The Hurt Locker), while Farmiga and Kendrick are nominated alongside Diane Kruger (Inglourious Basterds), Penelope Cruz (Nine) and Mo'Nique (Precious: Based On The Novel Push By Sapphire).
However, Up In The Air was snubbed in the overall cast prize - instead, the stars of Nine, Inglourious Basterds and Precious: Based On The Novel Push by Sapphire will be among the contenders for the ensemble award.
Other nominees include Sandra Bullock (The Blind Side) and Meryl Streep (Julie & Julia) in the best actress category, while Matt Damon (Invictus) and Woody Harrelson (The Messenger) are up for the best supporting actor honour.
The nominations were announced on Thursday morning (17Dec09) by Michelle Monaghan and Chris O'Donnell and the prizegiving ceremony will take place on 23 January (10).
The full list of movie nominations for the 16th Annual SAG Awards is as follows:
Outstanding Performance by a Male Actor in a Leading Role:
Jeff Bridges - Crazy Heart
George Clooney - Up In The Air
Colin Firth - A Single Man
Morgan Freeman - Invictus
Jeremy Renner - The Hurt Locker
Outstanding Performance by a Female Actor in a Leading Role:
Sandra Bullock - The Blind Side
Helen Mirren - The Last Station
Carey Mulligan - An Education
Gabourey Sidibe - Precious: Based On The Novel Push By Sapphire
Meryl Streep - Julie & Julia
Outstanding Performance by a Male Actor in a Supporting Role:
Matt Damon - Invictus
Woody Harrelson - The Messenger
Christopher Plummer - The Last Station
Stanley Tucci - The Lovely Bones
Christoph Waltz - Inglourious Basterds
Outstanding Performance by a Female Actor in a Supporting Role:
Penélope Cruz - Nine
Vera Farmiga - Up In The Air
Anna Kendrick - Up In The Air
Diane Kruger - Inglourious Basterds
Mo'nique - Precious: Based On The Novel Push By Sapphire
Outstanding Performance by a Cast in a Motion Picture:
The Hurt Locker
Precious: Based On The Novel Push By Sapphire.