The 43-year-old retired MLB star attended the New York premiere of Lopez's movie Second Act at Regal Union Square theater.
Rodriguez and Lopez looked the happy couple as they posed for photos together. Lopez stunned in a bright pink Giambattista Valli dress with a long train.
Rodriguez shared a photo with Lopez on Instagram ahead of the premiere, adding heart and star-eyes emojis.
"I think she was inspired by my Pink Panther look," he wrote. "Headed to the @SecondActMovie premiere in NYC with my girl! Who's excited to see @secondactmovie in theaters on December 21st!?"
Rodriguez and Lopez confirmed their relationship in March 2017. Lopez teared up in an interview with The Tonight Show this week while discussing how Rodriguez is a caring and encouraging partner.
"He's come into my life and really contributed in such a way. He's so supportive, he's so loving," the star told host Jimmy Fallon.
"He's one of these people, he's like, 'Shine, be the best.' Some people try to dull you down, try to squish you down, and he's so not like that," she said. "And it's just so refreshing. It's just such a beautiful thing."
Second Act co-stars Leah Remini, Vanessa Hudgens, Treat Williams and Milo Ventimiglia, and opens in theaters Dec. 21. The movie centers on a woman (Lopez) who gets the chance to fulfill her career ambitions.
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Jennifer Lopez, Vanessa Hudgens attend 'Second Act' premiere