The model's teenager left fans doing a double-take when he shared a photo on Instagram on Friday and he could easily have been mistaken for his famous mum.
In fact, some of his followers thought the long-haired star of the snapshot was Elizabeth, 55.
WATCH: Elizabeth Hurley looks incredible on the beach in turquoise bikini
The 18-year-old shared a selection of photos to wish his female friend a happy birthday, including one of them on the beach.
Damian was shirtless and smiling at the camera in the picture and wore his long hair loose over his shoulders.
"He's your double," wrote one fan, while several also called them "twins".
Elizabeth and Damian have a close relationship and before he celebrated his milestone birthday in March, the swimwear designer admitted she wasn't looking forward to him leaving school.
Damian is the spitting image of his mum
She told Tatler: "I could have my millionth midlife crisis because it will be the first time in 18 years there are no half terms, no school holidays, no school runs or sewing name tapes.
"And of course, I embrace it, but it's a real milestone in Mummy's life."
Damian has followed in his mum's footsteps and has launched his own modelling career.
He's also a keen photographer and has snapped some of Elizabeth's best swimsuit snaps.
Elizabeth and Damian are very close
Damian adores his mum and on her birthday this year, he shared a photo on Instagram and captioned it: "Happy birthday to my twin!! my partner in crime forever i love you mama xxxxxx."
Damian’s father is the late Steve Bing. He tragically died by suicide in June.
At the time Damian addressed the devastating news on social media with a heartfelt message to his fans.
"This is a very strange and confusing time and I’m immensely grateful to be surrounded by my phenomenal family and friends," he wrote.
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