The 'Boom Clap' hitmaker recently performed for the 34-year-old socialite at the amfAR gala during Cannes Film Festival, and was shocked to see the blonde beauty singing along to her tracks.
She told BANG Showbiz: ''When I was performing I caught Paris Hilton's eye and she was singing the words to 'Break The Rules' back at me, but in the most Paris Hilton way, and I was like, 'Oh my god Paris you're great.'''
The 22-year-old singer said the moment was especially important to her as she has always found the 'The Simple Life' star ''super wonderful'', pitching Paris alongside ''fit'' Bill Murray as her favourite celebrities.
She explained: ''Paris Hilton has always captivated my brain, very much so. I think she's like the original Barbie and super wonderful. And really Bill Murray I think he's hilarious and great and fit.''
And although she performed a selection of tracks at the star-studded ball, Charli admitted she got to let her hair down later in the night to meet ''cool people'' including Marion Cotillard, before getting ''turnt up'' along with pal Rita Ora.
Speaking at BBC Radio 1's Big Weekend, she added: ''There were a few cool people there, I met Marion Cotillard and I think she's so beautiful and wonderful and such a talented actress and it's cool to meet her, she's really gorgeous and great so yeah, there were cool people there.
''The parties were good. I got pretty turnt up to say the least, so it was good.''
Performances from BBC Radio 1's Big Weekend Norwich 2015 are available to watch on demand on Radio 1's BBC iPlayer channel.
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