Fox, who won the Alfred Dunhill Links Championship and Ras Al Khaimah Classic in 2022, beat world number one Rory McIlroy (33) and US Open champion Matt Fitzpatrick (28) to the award, claiming 50% of the votes cast by DP World Tour members.
He is the first golfer from New Zealand to win the award since Michael Campbell (53) in 2005.
"It's not something that I expected ever in my career. I would like to say it's something I dreamed of, but you look at those names on the trophy and I don't count myself as one of those," said Fox, who was second in the 2022 DP World Tour rankings behind McIlroy.
"Last year I thought I had a chance but a few other guys played pretty well, Rory, Matt, Jon Rahm (28), especially at the end of the year... To have your peers vote for you makes it that extra bit special."
The Player of the Year award is named after the late five-time major champion Ballesteros of Spain.