Green and the rest of the field put in long stints after play was cut short the previous day due to heavy rain, which caused flooding at the Seowon Valley Country Club layout.
The West Australian - who is chasing a third LPGA title of 2024 - began Saturday's action with a two-shot lead at 12 under.
She improved to 16 under after completing the final nine holes of her second round.
But Green made a shaky start to her third round on Saturday afternoon with bogeys at the third, fourth and eighth holes - her first blemishes of the tournament.
Pacesetter Hannah Green finished strongly on a long day in South Korea. (AP PHOTO)
The 27-year-old then went through the back nine in four under - including a brilliant eagle at the par-5 15th - to sign for a two-under 70 and a three-round total of 18 under 198.
South Korean Yu Jin Sung carded the low round of the tournament, a nine-under 63, to vault to outright second at 16 under, a shot clear of South Africa's two-time Australian Open winner Ashleigh  Buhai (71).
Defending champ Minjee Lee (66) drained a long birdie putt on the final hole to improve to a tie for 18th at 10 under 206.
Gabriela Ruffels (70) was the next best-placed Australian in a tie for 39th at five under.
The field in the $US2.2 million ($A3.3 million) event is loaded with eight of the LPGA Tour's top 10 players. It also includes 17 of the 18 winners this season on the tour.
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