The party was celebrating the kick-off of the Governors Ball Music Festival, with attendees including Chace Crawford and Anna Kendrick.
Olivia has topped our style crush list for ages, and it's easy to see why!
The socialite looked glam as she spruced up her black top with a sequin jacket and a whole lotta wrist bling.
But the part of her outfit we were most coveting was her loud-and-proud zebra-print miniskirt, which showed off her enviable pins perfectly.
And Miss Palermo proved you don't need heels to look sophisticated, as she donned faux snakeskin flats and still looked a million dollars.
Jealous? Us? Ok, maybe a little!
What do you think of Olivia's outfit? Let us know by commenting below as the best comment across the site each week wins £50!
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