Oppenheimer took the trophy for best movie cast at the honours handed out by members of the SAG-AFTRA actors union.
Cillian Murphy, who played scientist J. Robert Oppenheimer, was named best movie actor, and his co-star Robert Downey Jr. landed the best supporting actor prize.
The best actress trophy went to Lily Gladstone, star of the historical drama Killers of the Flower Moon. Da'Vine Joy Randolph won supporting actress for playing a grieving mother in The Holdovers.
The cast of Oppenheimer accept the award for outstanding performance by a cast in a motion picture. (AP PHOTO)
Earlier Australia's Elizabeth Debicki won the outstanding performance by a female actor in a drama series for her role as Diana, Princess of Wales in The Crown.
Debicki beat The Morning Show's Jennifer Aniston, The Last of Us' Bella Ramsey, The Diplomat's Keri Russell and Succession's Sarah Snook.
"Truly, I was not expecting this," the 33-year-old said. "The women in my category, I watch with total awe and I learn how to do my craft watching you. So being nominated next to you is incredible."
The Bear stars Jeremy Allen White and Ayo Edebiri collected the best actor and actress in a television comedy awards for their roles in the show about a gourmet chef trying to turn around his family's Chicago sandwich shop.
Ali Wong was named best actress in a limited series for road rage drama Beef. She thanked her 83-year-old mother who was in the audience.
"I know it was really hard when I told you I wanted to do stand-up comedy, and I hope you feel like it all worked out," she said.
SAG-AFTRA's film choices are closely watched because actors form the largest group of voters for next month's Academy Awards, the film industry's top prizes.
Barbra Streisand was honored with the SAG Life Achievement Award in recognition of her prolific career and humanitarian work.
The 81-year-old Streisand received SAG's highest award from Jennifer Aniston and Bradley Cooper. She was the 59th recipient of the award, which goes to an actor who fosters the "finest ideals of the acting profession." She was received with a standing ovation and many actors in tears.
Streisand recounted her dream of becoming an actress as a teenager in Brooklyn and being in awe of actor Marlon Brando in the 1955 film Guys and Dolls.
"That make-believe world was much more pleasant than anything I was experiencing," she told the crowd.
"I didn't like reality. I wanted to be in the movies even though I knew I didn't look like the other women on the screen. My mother said, 'You better learn to type,' but I didn't listen."
The SAG Awards were streamed live on Netflix, a first for a major Hollywood award show. That made for some significant tweaks to the age old traditions of such ceremonies. There were no ads. Profanity was permitted. And winners were occasionally interviewed backstage by red-carpet co-host Tan France - sometimes awkwardly, sometimes charmingly.
Agencies
