Marisa Baena carded a 1-under 70 to join Hee-Won Han in second place at 11- under-par 273. Heather Bowie fired a 5-under 66 to climb into a tie for fourth place. She was joined there by Mi Hyun Kim at 10-under-par 274.
Pak, who completed her third round Sunday morning at Highland Meadows Golf Club after storms halted play on Saturday, had a steady front side. She dropped a pitching wedge within seven feet to set up birdie at the par-3 sixth.
The South Korean followed that up with kick-in birdie at the par-5 seventh after sticking a sand wedge one foot from the hole. She cruised to the back side from the there.
However, the back nine was unkind to Pak. She missed the green at the par-3 14th and failed to save par, which dropped her to minus-14.
At the 16th, Pak lost her drive right. She pitched out and her third came up short in a bunker. After blasting out, it took two putts to get down and the double bogey dropped her into a share of the lead with Han.
Pak rolled in a five-footer at the 17th for birdie and a one-stroke lead. Han bogeyed the last for the final margin. Pak won for the fourth time at this event to go along with titles in 1998, 1999 and 2001.
'I felt great the whole week actually,' said Pak, who picked up $150,000 for the win. 'I was really excited to play this tournament. This is always exciting and something special, so I am really happy to win again.'
Han began the final round one stroke behind Pak. She dropped a shot at the first, but came back with three birdies over her final five holes on the front side.
On the back side, she bogeyed the 10th and 12th but came back to birdie No. 14. She stumbled to another bogey at the 15th and also bogeyed the last to finish two shots back.
Baena bogeyed the first, but came right back with birdies at the second and fourth. She made her third birdie of the day at the sixth from 12 feet out. She settled down to run off eight straight pars.
The Colombian stumbled to back-to-back bogeys from the 15th. She got one stroke back with a birdie on No. 17 but Baena was just glad to be here at all.
'It was great to even play this week,' Baena said. 'Last week on Tuesday, I got up and had tendinitis in my wrist. I couldn't even close my hand. I had to get a cortisone shot that morning and had to pull out of last week's event. Overall, I am extremely happy and thrilled with my week.'