The actress, 33, was a vision in a sizzling semi-sheer black corset and a unique pair of oversized corduroy pants, as she commanded attention at the event, held at the Ace Theatre.
The Barbie star left her trousers slightly unbuttoned for a trendy look that showed off her trim waist.
The beauty wore her blonde tresses parted in the middle and cascading down in light waves, as she posed for snaps alongside her spouse, 33.
Her husband-of-six-years looked handsome in a tan double-breasted suit jacket with shoulder pads, underneath which he sported a black tee.
At the event the duo posed for snaps with producer Josey McNamara, who matched Tom in a tan suit.
Margot also mingled with Carey Mulligan, 38. Carey stunned in a tuxedo-inspired top and shimmering silver and black skirt, which she paired with satin black pumps.
Later on she also posed with Amazon Studios head Jennifer Salke, and the film’s director Emerald Fennell.
Jacob Elordi, 26, was also present at the premiere, and rocked a stylish brown satin three-piece suit.
It was styled with a classic white button-up shirt, skinny black tie and patent leather dress shoes.
Margot met Tom while shooting Suite Francaise, on which he was assistant director, and she insisted even looking ‘hideous’ in the film didn’t put him off.
She previously told the Daily Mirror newspaper: ‘I have been so fortunate to have some amazing opportunities.
‘I did Wolf of Wall Street and then got to do something completely the opposite in Suite Française – I was a peasant farm girl and looked hideous but I met my husband on the job so it was OK.
The couple went on to form a production company, Lucky Chap, with their friends, and Margot feels ‘very lucky’ because of the bond they share.
The Suicide Squad star said: ‘We started our production company with our best friends and it continues to be a wonderful group dynamic. We all really work well together. I feel very lucky.’
Notoriously private Margot rarely speaks about her marriage to Tom. The couple have been married since 2016.
In an interview with Elle in 2018, blonde beauty Margot admitted that she and Tom had initially decided to keep their romantic relationship to themselves.
She said: ‘We kept it a secret. Because we weren’t really taking it seriously. ‘Oh, whatever, we’re just mates, we’re just mates.’ And then… everyone found out.’
‘It was dramatic,’ she recalled of the moment her friends found out. ‘I’m not going into the details, but s**t hit the fan.
‘Our house turned into The Jerry Springer Show for a moment there. But then the dust settled, and it was all good.’
Her new film Saltburn centers around Oliver Quick (Barry Keoghan), and his aristocratic friend – Felix Catton – played by Jacob Elordi.
The film, written and directed by Academy Award-winner Emerald Fennell, is set in England, with the two young men attending Oxford University in the mid-2000s.
Emerald previously wrote and directed Promising Young Woman; she won an Academy Award for Best Original Screenplay, and was nominate for Best Director and Best Picture.
Rosamund Pike, Richard E. Grant, Archie Madekwe and Richard E. Grant also star in the project by Amazon Studios and MGM Studios, produced by LuckyChap Entertainment – Robbie’s production company.
Saltburn will arrive in theaters on November 24.