In the other semifinal match, Ya-Ni Tseng defeated In-Bee Park, 1-up, to earn a spot in the championship match against Wie.
Wie, who became the youngest person to ever win a USGA adult championship when she captured last year's event at Ocean Hammock Golf Club in Palm Coast, Florida, disposed of Jenna Pearson, 5 and 4, in Saturday morning's quarterfinals and found herself trailing early on in her afternoon match.
Angela Park birdied the par-4 third to 1-up briefly, but Wie answered with a birdie at the very next hole to square the match.
Wie then birdied the fifth and won the sixth with a par to go 2-up. Park battled back with a birdie at the eighth, but Wie went 2-up again with a birdie at the par-3 11th.
Park persisted, however, and won two holes in a row starting at the 12th to again square the match. Wie proved to be too much in the end though, and won the 14th with a birdie, before picking up a par at the 17th to close out the match.
'Angela played superbly, but a lot of people expected a lot of me this week,' said Wie. 'When I got here my picture was on the program. My heart was in my lungs the whole time. I really want to win this tournament. I made it this far and I don't want to drop it in the end.'
Tseng took care of Hannah Jun, 7 and 5, in the morning matches, and quickly got to work on In-Bee Park in the afternoon, going 3-up after a win on the fourth hole.
Park, who ousted medalist Brittany Lang in the quarterfinals, never had a lead in their match, although she got 1-down on several occasions. Tseng birdied the par-five 15th to go 2-up, but Park countered with a win at the 16th. The duo halved the 17th and 18th holes, ultimately granting Tseng a pass to the final.
'I didn't realize I could get this far,' said Tseng. 'In Chinese Taipei, we just started playing a match-play format last year.'
Wie and Tseng will battle it out in the 36-hole final match to determine the winner.