The actress, 41, posed for the cameras alongside the 10-year-old, whom she shares with former partner Tom Sturridge.
They were sat at the Proenza Schouler show alongside Vogue editor Anna Wintour, with White Lotus star Meghann Fahy and model Karen Elson also in attendance.
Miller looked typically chic in a cream short-sleeved top, black miniskirt, chunky black heeled sandals and a pair of retro-stye sunglasses.
Meanwhile, Marlowe, who is being raised predominantly in Buckinghamshire, wore a grey suit, monochrome trainers and black sunglasses.
Her actor parents were together from 2011 to 2015, during which time they were reported to have been engaged.
In November, Miller told Vogue that she had "wasted time" trying to tick off marriage and motherhood in her thirties.
She said: "I'd invested what felt like the important years in something that was just a bucket with a hole in it of a person. I wasted time. And I felt like time was really my currency."
Speaking of her thirties, Miller said: "There was a lot of anxiety. Relationships hadn't worked out – I imagined that I would be married with three kids, being a great mum."
However, she added: "I love being a mother. It's what I do best."
The Anatomy Of A Scandal star remains friends with her daughter's father, who is now dating the model and presenter Alexa Chung.
Miller previously dated Jude Law, who she was with from 2003 to 2005, before they rekindled their relationship from 2009 to 2011.
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