Second seed and US Open champion Gauff came through 6-1, 6-2 in just 64 minutes on Centre Court, avoiding a repeat of 12 months ago, when she was dumped out in the first round by fellow American Sofia Kenin.
Earlier Monday, third-ranked Australian Open champion Aryna Sabalenka withdrew from the tournament with a shoulder injury.
Eighth-seeded Zheng Qinwen was knocked out by New Zealand qualifier Lulu Sun.
Both women were in Gauff's side of the draw and potential opponents in the last four.
"Wimbledon is the place where I believed that the dream was possible," said Gauff, who made her breakthrough at the tournament in 2019 when she reached the fourth round as a 15-year-old qualifier.
"I've played on a lot of big courts but every time I play here I feel even more nervous -- even more than in a Grand Slam final."
