He joined her at her concert in Paris earlier this week and she has been pictured sporting a huge sparkler -- though she's denied reports that they've got engaged.
In a message to all her Irish fans, she wrote on her Twitter page: "Excited to play my first show in Ireland and see all my fans at the O2 Dublin. Who's coming?"
She then added how there's still a "few tickets" left and included a link to the Ticketmaster page.
It's her first time performing here -- she's been taking Europe by storm with her Dance Again world tour and performed in Paris on Wednesday night before touching down in Ireland with her huge entourage.
The star, (43) who has sold more than 55 million albums worldwide, will be thrilling fans at the northside venue this evening as she draws on her lengthy repertoire of hits spanning the past two decades.
Irish ticket-holders can expect to see a dizzying array of costume changes as she shows off her perfect figure in a string of glitzy outfits.
Speaking about the show, J Lo said: "It's gonna be a really, really high-energy-filled, amazing show and I'm excited about that. It's pretty awesome."
She added: "A lot of times fans will be into the music of two or three [acts] and when you bring the right package together, it's a really great experience for them."
And the star of The Wedding Planner, who's famous for her backstage demands, has stood by her decision to be choosy about her preferences.
She insists her demands aren't as unusual as people think.
"I think people love to look at them (riders) and go, 'Oh my God she wants M&Ms -- she's crazy!'
"I think everyone has their list of things that make you feel comfortable -- like a certain kind of potato chip or water. I think the crazy ones are made up," she said.
She has thrown herself into her career over the past year since splitting from her husband Marc Anthony in July 2011, with whom she has four-year-old twins Max and Emme.
And she credits a lot of her success to her clean-living lifestyle and her teetotal ways, saying that her mum always instilled a distaste for alcohol in her.