According to the labour ministry, the number of registered job seekers without any employment activity increased in August by 20,000 people — or 0.6 percent — compared to July, when their ranks decreased by 0.1 percent.
That rise brought the total number of partial or fully unemployed to 3.57 million people.
With the jobless rate currently at 10 percent in the eurozone's second-largest economy, President Francois Hollande has staked his political future on reducing unemployment, saying he will not stand for re-election in 2017 unless he reverses a trend that has generally been on the rise for the better part of a decade.
Hollande has acknowledged that reducing unemployment will be difficult against growth forecasts set at just one percent this year and 1.5 percent in 2016.
Most economists view annual expansion of 1.5 percent as the minimum required to reduce joblessness.
Since Hollande took office in 2012 amid the eurozone's enduring debt crisis and economic lethargy, a total of around 650,000 people have registered as unemployed in France.
The August figures brought the number of people without any work up to a total 4.4 percent increase for the past year.
The total number of the long-term unemployed, meanwhile, rose by 0.8 percent to 2.4 million people last month, part of a whopping 18.6 percent rise in that category over the past year.