Ko fired a 68 in the final round and then dispatched Julieta Granada and Carlota Ciganda in a playoff.
The million-dollar bonus for winning the "Race" got Ko's attention.
"When I saw that $1 million in the box," she said, "I was like, 'Wow, I wonder who the winner of that will be?' It's amazing. I've never seen that much cash in one place before.
"This year has been awesome. Three wins, Rookie of the Year, it's a huge honor for me to be here in this position. I'm looking forward to what's coming up next year."
Currently ranked No. 3 in the Rolex Rankings, Ko has yet to miss a cut in 42 starts on the LPGA Tour and now has five career victories, two coming as an amateur.
It was also a great year for Stacy Lewis, who finished second in the Race to CME Globe. The world No. 2-ranked Lewis won three LPGA titles in 2014 and took home Rolex Player of the Year, the Vare Trophy (awarded to the player with the lowest scoring average) and the LPGA money title.
"That’s what I came here for," Lewis said. "I went into the week wanting to win these three awards. The $1 million and all would’ve been nice, but I would take these three over $1 million any day."
Lewis is the first American player to sweep the three honors since Betsy King did it in 1993. Yani Tseng, in 2011, was the last player to pull off the triple.