The 28-year-old unseated Korea’s Sung Hyun Park with a one-shot win over Thailand’s Moriya Jutanugarn at the Blue Bay LPGA tournament in her home country.
Feng, who became the first Chinese player to win a major when she took out the Women’s PGA Championship in 2012, was overwhelmed by the achievement.
“You're sure?” was her first response when told the news immediately after the tournament.
When told it was the projected outcome she couldn’t contain her excitement.
“Well, the media has been asking me yesterday. They were like: What will you feel like if you get to world No. 1 and what can it do for Chinese golf? Now I can answer.
“Of course, I'm really, really excited and very proud of myself and I think it's special because I won this tournament to become world No. 1.
“I finished first in China, so I actually claimed the world No. 1 in front of all the people at home.“So I'm really happy about that, and I hope all the Chinese are going to be watching me and the Chinese can play golf.
“Hopefully there will be more Chinese getting on the tours and more world No. 1's coming up from China.”
Feng outlasted Jutanugarn in a tense final round battle which went all the way to the final hole.
Feng held a one stroke lead when both players dropped shots at the difficult par-3 17th and Jutanugarn had a putt to force a play-off at the par-5 last but her effort slid past the cup.
The pair had separated themselves from the field over the final 18 holes and the back nine was a race between two with a two-shot swing at the 13th hole proving the pivotal moment.
All square after 12, Jutanugarn made a costly bogey to Feng’s birdie and despite clawing back one shot at the next the margin remained one until the finish.
For Jutanugarn it was the latest in a string of close calls but the Thai star was philosophical about the result.
“You know, I made a lot of good putts, a lot of good shots out there,” she said.
“I'm pretty happy with what's happened. I was just trying to give myself a chance.
“As long as I try to give myself a chance, I think it's a pretty good thing to do.”
It was Jutanugarn’s sixth top five finish of the season, the 23-year-old still in search of her first LPGA victory.
Sarah Jane Smith was the best of the Australians in the field rallying to a T14 finsih with a 2-under 70 in the final round.
Defending champion Minjee Lee was T25 at 5-over for the week, one ahead of fellow Olympian Su Oh whose 6-over effort saw her finish T30.
CHINESE ACE ZECHENG DOU MAKING A NAME FOR HIMSELF:
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