Rebensburg navigated the soft but stable course in a combined-run time of 2 minutes, 33.3 seconds, 0.06 seconds ahead of Slovenia's Maze and took possession of the top spot in the giant slalom standings.
"I didn't have a good feeling on the course in the second run," said Rebensburg, who was cheered on by her homeland fans. "I actually thought I was behind, but it turned out well."
Irene Curtonia of Italy took third place Friday with a 2:34.04, and Tessa Worley of France, who started the day atop the GS standings, finished seventh. Americans Julia Mancuso and Lindsey Vonn took ninth and 10th places, respectively.
The course at Ofterschwang was softened up by warm weather that was expected to persist across southern Bavaria into the weekend when the women will compete in another giant slalom on Saturday and slalom on Sunday.