The 24-year-old’s 18.53 point score was more than enough to beat the promising teenager, who posted a respectable 13.10.
Gilmore has now won more major titles than any other woman, lying level with and Layne Beachley (five) with only all-time great Kelly Slater (11) ahead of her.
“I woke up this morning and thought it wouldn’t happen today,” Gilmore said. “But as the day progressed, and things fell into place, I began to believe it could happen.
“France is such a special place and having so many people on the beach watching us surf today is really emotional. I think I’m going to cry.”
Gilmore’s first four titles came between 2007 and 2010 but she fell back to world number three last season.
“This year for me was all about improving my consistency and having fun with my surfing,” Gilmore added.
“From when I started five years ago to where we are now, women’s surfing has improved so much. It’s an honour to be back up top as these girls push me everyday and are all incredible surfers.”