The single actress looked stunning in a black dress as she enjoyed the star-studded bash.
DiCaprio celebrated on Friday night at the Spring Place members-only club in Beverly Hills.
Aniston, 49, was spotted having a good time at the party where she talked with her friend Jennifer Meyer.
Around 500 people were invited to the party with a more intimate dinner for 50 people too.
DiCaprio has been dating girlfriend Camila Morrone, 21, for the past six months.
The couple celebrated his birthday all weekend.
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