Alex Morgan scored twice and Abby Wambach and Carli Lloyd added single strikes for the Americans, who allowed a pair of goals in just over two minutes and trailed 2-0 by the 14th in the match played at Hampden Park in Glasgow, Scotland.
CONCACAF's other participant, Canada, gave up two first-half goals to reigning Women's World Cup champion Japan and lost 2-1 at Ricoh Arena in Coventry, England.
Gaetane Thiney gave France the lead with a 25-meter strike and Marie-Laure Delie added another goal from a loose ball after the United States was unable to clear a corner kick.
But Wambach responded for the United States with a header off Megan Rapinoe's corner kick in the 18th and Morgan equalized with her first in the 32nd, lifting a Hope Solo free kick over French keeper Sarah Bouhaddi off the bounce.
Lloyd, who replaced the injured Shannon Boxx in the 17th minute, matched Thiney's effort with a 25-meter drive of her own in the 56th. Morgan ensured the victory 10 minutes later, tapping in at the right post after Rapinoe sent Tobin Heath on a long run down the left.
The victory extended the Americans unbeaten run to seven straight since losing to Japan in the Algarve Cup in Match, and 14 straight against France. It has won 13 of 14 meetings against the French with one draw.
Canada's loss was its second straight, having lost its last Olympic prep match, 2-1 to Brazil, on July 17.
In Coventry, Nahomi Kawasumi and Aya Miyama scored first-half goals to give Japan the lead.
Melissa Tancredi took a feed from Rhian Wilkinson and replied in the 54th for Canada, which lost its third straight at the Olympics. Canada also lost all three games at last year's Women's World Cup, where it was outscored 7-1.
With Karina LeBlanc reportedly suffering from a sore ankle, Canada played with Eric McLeod in goal.