Iestyn Harris' men led 6-0 thanks to an early try from full-back David James but they were undone by a three-try burst in a pivotal six-minute spell inspired by man of the match Thomas Bosc just before half-time.
Wales, led for the first time by Craig Kopczak, will now need to beat tournament favourites England in Wrexham next Saturday to keep alive their hopes of reaching the November 11 final in Salford.
The Welsh, who gave a debut to Wigan reserve Rhys Pugsley on his 18th birthday, silenced the 11,628 crowd at Stade Felix Bollaert by making a dream start following a knock-on by France skipper Olivier Elima on his own 20-metre line.
Half-backs Danny Jones and Matty Seamark took full advantage, combining superbly to get James over for the game's first try with just 100 seconds on the clock. Seamark's conversion made it 6-0 but France went on to dominate the rest of the half and fluffed two glorious tryscoring opportunities before finally opening their account.
Left winger Clement Soubeyras had a try disallowed for a forward pass from his centre Kevin Larroyer and right winger Mathias Pala dropped the ball from Bosc's high kick with the line at his mercy.
The misses began to look costly until the French struck with three tries in the last nine minutes of the first half.
Substitute Romaric Bemba won the race to Bosc's kick to the line to score with his first touch, full-back Cyril Stacul took the stand-off's pass and bounced off an injured Christian Roets to add a second and Bosc went over himself following a break by his half-back partner William Barthau.
Bosc added all three conversions to put his side into an 18-6 lead at half-time and they ought to have scored again early in the second half when Pala broke clear but Elima could not take the final pass.
Wales were reduced to 12 men on 50 minutes when Gil Dudson was sin-binned for a late tackle on Barthau that sparked a flurry of punches and Bosc extended his side's lead with the resultant penalty. However, the Welsh kept their line intact until Dudson returned for the last quarter and they attacked the French line with venom, although without managing to make another breakthrough.