Wozniacki, who will make her fifth appearance at the Oct. 22-29 event, reached the final in 2010 when Doha hosted the WTA Finals.
"I'm very excited that I've qualified for the WTA Finals again," the 27-year-old Wozniacki said in a statement.
"I have such great memories of the tournament, especially from 2010, and I can't wait to get to back to Singapore and play my best tennis in front of the amazing fans there."
The top eight singles players at the $7 million prize money event will face off in a round-robin format for the Billie Jean King Trophy.
The eight best doubles teams will battle for the Martina Navratilova Trophy in a knock-out format.
Wozniacki, who has 26 career titles, is due to play local hope Wang Qiang in the first round of the China Open later on Sunday in Beijing.
(Reporting by Shrivathsa Sridhar in Bengaluru; Editing by Greg Stutchbury)
