Wearing nothing but pink underwear and a hat, the 34-year-old is seen in the mirror-selfie using only her arms to cover her chest. She has one message: "Just so you know with me, it's all real, all the time."
"Felt like it was time to start sharing some personal stuff with you guys … And it's just the beginning. Night night. X," Aguilera captioned the photo.
It is unclear what "personal stuff" is to follow, but the mother of two is definitely off to a revealing start with the photo, showing off her toned figure nearly a year after the birth of her daughter, Summer Rain.
Aguilera, who is on a break from NBC's The Voice this season, isn't the only star to take it off on social media this week.
On Tuesday, Kim Kardashian West shared a nude pregnancy photo on Instagram to slam body-shamers.