It was the fifth giant slalom win of Meillard's career. The 29-year-old climbed from fifth after the opening run to secure the top spot with precision and composure.
"It's amazing," Meillard was quoted as saying on the International Ski and Snowboard Federation website.
"Fourth place would have been pretty amazing today, a good step in the right direction. But to win directly, it's simply perfect.
"It shows the work we've been putting in the last two weeks with the team. We've worked on a few small (things) in the end, nothing big, but just finding the right movement again, the flow, and today it worked.
"With Odi (Odermatt) I'm used to doing podiums with him, but Luca, his first podium in GS, he's been working hard the last two seasons."
Odermatt, the reigning Olympic giant slalom champion, arrived in Val d'Isere after winning two of the first three giant slalom races this season, including last weekend's triumph at Beaver Creek.
This time, he faced a sterner test. Fourth after the first run and 0.46 seconds behind leader Stefan Brennsteiner, Odermatt struggled with mistakes in the decisive second leg and ultimately settled for third, 0.33 seconds behind Meillard.
"With those two runs I'm not actually happy with my skiing, but to end up on a podium with two friends on the top, that's an amazing day," four-times overall World Cup champion Odermatt said.
"It was a tough week, with the jet lag, with coming back to different snow. It was not that easy today to get into this 100% race focus. But still, I skied down twice with a fight, and luckily it was enough for the podium."
Odermatt, 28, is a leading contender for multiple medals at the Milano-Cortina Winter Olympics in February.
Austrian Brennsteiner, who had set the pace in the opening run, was unable to maintain his rhythm and slipped to fifth on La face de Bellevarde, one of the most demanding courses on the Alpine Ski World Cup circuit.
The Val d'Isere weekend continues on Sunday with the men's slalom, before the World Cup tour moves to Val Gardena/Groden for a three-day stop beginning on December 18th.