In mixed conditions, the Ford Fiesta RS WRC driver set a time of 2m26.1s for the two-mile stage close to Valence.
Sebastien Loeb was second fastest in his Citroen DS3 WRC, 2.6 seconds down on the flying Belgian.
Neuville said: "Of course it's always a good feeling to be fastest, but it's the next four days that really count.
"Every time I get behind the wheel of the Fiesta I am feeling more and more confident and, hopefully, I can carry this speed to into the rally and bring home a good result."
Shakedown for the opening round of the 2013 WRC bears little resemblance to the Alpine roads on which this event will be fought.
"The shakedown stage went around a field, but with the conditions it was quite lucky - I think everybody went into the field today..." said Loeb.
"But tomorrow, when the rally really starts, then we are no longer in the field, but we are driving with the rocks and the ditches. Tomorrow, everything starts."
Neuville's team-mate Evgeny Novikov was third quickest in his Fiesta - just one tenth behind Loeb - with Mikko Hirvonen fourth in another Citroen.
Jari-Matti Latvala was fastest of the Volkswagen Polo R WRCs in fifth, 4.3s down on Neuville, and one place and one tenth ahead of VW team-mate Sebastien Ogier.