The 37-year-old singer posted a photo on Instagram of himself kissing and embracing Biel during a nighttime outing along the Seine River.
Biel was all smiles in a grey top, black pants and Chanel bag, while Timberlake sported a t-shirt, denim shirt and jeans. The Eiffel Tower can be seen in the background of the snapshot.
"Midnight," Timberlake captioned the post.
Timberlake and Biel arrived in France during a short break in the singer's Man of the Woods tour. Timberlake will kick off the second leg Tuesday in Paris, and appeared to tease a new song Tuesday morning on Instagram.
"Very ready to kick off the European leg of the tour tonight in [France]," he captioned a video.
Timberlake and Biel married in October 2012, and are parents to 3-year-old son Silas Randall. Biel gushed about Timberlake in a post on Father's Day in June.
"Here's to my amazing father who taught me not to be afraid of anything! TO be strict and diligent about personal discipline and integrity, who loves me desperately and nurtured all my childhood and adult dreams," the actress wrote.
"And to my husband who I watch with awe everyday as he guides and teaches, encourages and supports, and above all, LOVES the [expletive], out of his own young man," she added. "Happy Father's Day to all the dads out there. We can't do this parenting thing without you."