France’s five tries came via centre Gael Fickou, scrumhalves Nolann Le Garrec and Maxime Lucu, prop Georges-Henri Colombe and Romain Taofifenua.
While it was a far from perfect performance, under pressure coach Fabien Galthie will be relieved with the win.
"We had a great performance today, we were really frustrated after Italy and wanted to make France proud again so it's great to do that at this stadium," France captain Gregory Alldritt said.
"We have a massive massive pack, and we wanted to be tough on the collision. We have some really good young players and I'm really proud of them and that Nolan Le Garrec scored a try as well."
Wales have now been victorious in only one of their last 12 Six Nations matches but were in the game for an hour as they scored tries through wing Rio Dyer, scrum-half Tomos Williams and centre Joe Roberts.
They have lost all four games in this year’s championship as coach Warren Gatland rebuilds the team, and will hope to avoid a fifth in their final match against Italy at home next Saturday.
France move to 11 points from their four games, five behind leaders Ireland. They must beat England with a bonus point in Lyon next Saturday and hope Scotland upset the Irish in Dublin to stand a chance of lifting the trophy, though their inferior points difference will count against them.
France made eight changes for the game and had three debutants in their starting lineup in lock Emmanuel Meafou fullback Leo Barre and centre Nicolas Depoortere.
They looked disjointed at the beginning as Wales made a bright start, but as their heavy pack took its toll on the hosts, France showed their superiority with three unanswered tries in the final quarter of the game.
The French have been below par in this Championship and escaped with a fortunate draw at home to Italy last time out, so Galthie will now hope this pressure release is followed by another against England.
The teams traded penalties before Dyer scored the game’s opening try, spotting a gap in the French defence and bursting through to run the ball in from 40 yards.
France continued to see more of the ball though and their relentless battering of the Wales defensive line paid dividends midway through the first half as they spread the ball wide having created the space for Fickou to score in the corner.
Wales’s response was almost immediate. Centre Owen Watkin barged through a couple of feeble French tackles and fed Williams for an easy score.
Thomas Ramos, playing at fly-half for the first time for France after an injury to Matthieu Jalibert, was one of the guilty parties.
The seesaw pattern of scoring continued as France went over the tryline next, a solid scrum five metres from the Welsh line led to Le Garrec sniping over as they led 20-17 at halftime.
Wales regained the lead early in the second half when Roberts scored, but the French pressure became relentless as Wales conceded a succession of penalties in their own 22.
After closing the gap to a single point, Colombe, Taofifenua and Lucu added further scores as Wales wilted.
Hooker Evan Lloyd came off the bench for the home side late on having played only two hours of professional rugby in his career, and never started a game.
"We felt like the French would fatigue later on with their big pack. It didn't go to plan but we'll look at it and come back next week," Wales captain Dafydd Jenkins said.
"We were excited about the physical battle but we definitely came off second best. Next week is massive for us because we don't want to finish bottom."
