The 20-year-old, who was awarded the 2011 Mark H. McCormack Medal as the world's number one amateur, will make his first appearance as a pro at this week's Travelers Championship in Cromwell, Connecticut.
Cantlay, who has recorded four top-25 finishes in eight appearances on the U.S. PGA Tour, has signed with the same agent who represents Tiger Woods, Mark Steinberg of Excel Sports Management.
"I have a tremendous passion and respect for the game of golf and can't wait for the challenge of taking my game to the next level," Cantlay said in a statement.
A sophomore at the University of California, Los Angeles, Cantlay decided to forego his final two years there to become a golf professional.
"I am so grateful to UCLA ... for the relationships I've formed and the opportunities I've had to compete and develop at the collegiate level," said Cantlay, who was runner-up to compatriot Kelly Kraft at the 2011 U.S. amateur championship.
Cantlay made a big splash on the PGA Tour last year, tying for 21st as the low amateur at the U.S. Open, sharing ninth place at the Canadian Open and firing a course record 60 at the Travelers Championship on the way to a joint 24th finish.
He also clinched the 2011 Southern California Golf Association amateur title and helped his college team win four tournaments last year while also finishing second at the prestigious Western amateur championship.
Two months ago, Cantlay finished as low amateur at the Masters with a share of 47th place.