Fifty certainly looks fabulous on her as the mum-of-two partied like she was half her age, taking to the dance floor to sing and have some hardcore dance offs to the DJ line up, which included DJ Cassidy.
DJ Khalid and Fat Joe also thrilled guests with impromptu performances, and Ashanti came out to sing 'What's Love' for the partygoers.
According to an Us Weekly source, J-Lo "was dancing and singing along to every word."
“The big surprise performance was done by J-Lo’s daughter,” the insider dished of the superstar’s 11-year-old daughter, Emme, who performed 'Mahogany' by Diana Ross.
“J-Lo was seated right up front to watch her and was both crying and was beaming with pride, she gave them a huge hug after.” (Lopez shares twins Emme and Max, 11, with her ex-husband Marc Anthony.
After dinner, a huge firework display lit up the Miami sky, signalling the start of the dance party.
According to sources, J-Lo and Arod were the last to leave the party, staying until 2:30 am.
J-Lo spoke to WHO last year about her plans for the future, and her vision of marriage and relationships.
"I always thought, again, ’cause of the way I was raised, that when you fall in love with somebody, you get married and you try to have a life together.
"And I learned along the way that’s not really how it works; it takes more than that. So you have to choose well and there’s a lot of different things.
"I love the idea of growing old with somebody and being committed to them and declaring that to one another, not so much to the world, but to one another," she shared.