Nikki's boyfriend, producer Chuck Pacheco, Hilary Duff, Tom Hardy, and Paris Hilton were a few of the stars that joined the rumored lovebirds.
Leonardo also joined in on the birthday festivities, as he was photographed standing with other party-goers as they watched Nikki cut her birthday cake.
Later he and Rihanna reportedly headed to the same after party, where The Wolf of Wall Street star ran into 50 Cent.
The rapper posted photographs with the actor to his Instagram account, along with shots of model Naomi Campbell, who was also in attendance.
This isn't the first time that that handsome bachelor and the Umbrella hitmaker have been spotted partying together.
Leonardo and Rihanna were both in St. Barts for New Year's Eve, and it was reported that they both celebrated at La Plage Club.
Rihanna posted numerous photos of her vacation on Instagram, but refrained from sharing anything from New Year's Eve.
Neither Leonardo nor Rihanna has spoken about their relationship, either to confirm or deny the host of rumors.
However, in an August interview with Elle Magazine Rihanna mentioned the actor as a source of inspiration.
When asked if she had any words to live by, she responded: "Avoid obviousness. That is a quote by Leonardo DiCaprio."
"That's what makes you create something, that's the excitement, that's the thrill," the artist elaborated.
- Daily Mail
