Dumerc averaged 14.3 points and 3.4 assists while captaining France to a silver medal in the 2012 Olympics and was named FIBA Europe Women's Player of the Year later that year.
"We're thrilled to add Celine Dumerc, one of the best point guards in the world, to the Atlanta Dream roster," said Dream general manager Angela Taylor. "She is a great leader, and a prototypical point guard who makes players around her better. She's a dynamic playmaker in the open floor, a veteran leader, excels in up-tempo systems like coach (Michael) Cooper's and will be a nice compliment to the players on our roster."
Dumerc, 31, is a two-time EuroLeague All-Star and is currently averaging 9.8 points, 5.1 assists and 4.8 rebounds per game for Bourges.
The reigning Eastern Conference-champion Dream begin their season on May 16.