To honor JT's special day, we're taking a look back at all of his high-profile romances.
Let's just say he had a lot of practice in the relationship field before putting a ring on Jessica Biel's finger!
In the late 1990s, Timberlake rose to prominence as one of the two lead vocalists and youngest member of NSYNC, which eventually became one of the best-selling boy bands of all time.
Timberlake began to adopt a more mature image as an artist with the release of his debut solo album, the R&B-focused Justified (2002), which yielded the successful singles "Cry Me a River" and "Rock Your Body", and earned his first two Grammy Awards.
The former became the best-selling album of the year in the US with the largest sales week, and spawned the top-three singles "Suit & Tie" and "Mirrors", while the latter produced the top-ten song "Not a Bad Thing".
For his live performances, including the eponymous concert tour for the albums, he began performing with his band The Tennessee Kids, composed by instrumentalists and dancers.
From 2008 through 2012, Timberlake focused on his acting career, effectively putting his music career on hiatus; he held starring roles in the films The Social Network, Bad Teacher, In Time, and Friends with Benefits.
From relationship lows (rumors of Timberlake's infidelity) to total highs (the snowboarding pair love the mountains), check out a history of their relationship.
July 2011 - Present Justin Timberlake and Jessica Biel reportedly got back together over the summer of 2011, when they were photographed on vacation together and were seen out with the actress' parents.
Justin Timberlake ex-girlfriends list includes some of the most beautiful women in entertainment, including his current wife, Jessica Biel.
Before they made it official, they broke up for a few months in 2011.
During that time, he was linked to Scarlett, Olivia Munn, Mila Kunis, Olivia Wilde, Ashley Olsen..who's counting.