With nine strokes under par, the 26-year-old was the best of all during the second round when the women's US tour makes a guest appearance in South Korea.
After the first day, Grant was in a shared 63rd place after an initial par round, but after Friday, the Swede is in a shared 11th place.
Grant, who started on hole 10, was already after eight holes six strokes under par after four birdies and one eagle. There was not a single bogey throughout the round for a total of 63 strokes. Madelene Sagström is one stroke behind at –8.
However, before the weekend's two rounds, the distance to the top is long. The home player Kim Sei-Young is leading at –16.