The image, which has been taken from behind, shows Jennifer in a fairy-tale white gown, which features a cinched waist and voluminous skirt which cascades into a long train.
The off-the-shoulder design also boasts puffy sheer sleeves that perfectly compliment the princess-style dress.
WATCH: Jennifer Lopez looks incredible in hot pink swimsuit
Jennifer has her hair styled up, with loose curls left to fall about her face.
Despite causing much excitement with her Instagram photo, all is not what it seems. Jennifer was actually wearing the dress for her role in upcoming film, Shotgun Wedding.
The mother-of-two has been filming scenes in the Dominican Republic recently, alongside her co-star Josh Duhamel.
Jennifer Lopez surprised fans with her wedding dress photo
Earlier this month, Variety confirmed that Josh has replaced Armie Hammer in the wedding comedy. The president of production for the Lionsgate Motion Picture Group, Erin Westerman, said in a statement, "We couldn’t be happier for our bride and groom of this 'Shotgun Wedding'.
"We know Josh and Jennifer will make a compelling and sexy on-screen couple and they will be fun sparring partners as their dream destination wedding erupts into a memorable nightmare."
The star started dating Alex in 2017
A synopsis for the movie reads: 'A couple's extravagant destination wedding is hijacked by criminals. In the process of saving their families, they rediscover why they fell in love in the first place.'
Jennifer, 51, and Alex, 45, started dating in 2017 and announced their engagement in March 2019. The couple were forced to postpone their 2020 wedding due to the pandemic having planned to tie the knot in a ceremony in Italy in June.
Jennifer with her twins Max and Emme
This will be the singer's third time walking down the aisle, while Alex, 45, is preparing for his second time as a groom. Jennifer was notably married to Marc Anthony – father of her 13-year-old twins Max and Emme - from 2004 to 2014, Chris Judd from 2001 to 2003, and Ojani Noa from 1997 to 1998.
Alex's marriage to Cynthia Scurtis, meanwhile, lasted from 2002 to 2008, and together they share two daughters, Natasha, 16, and 12-year-old Ella.
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