Remesy and Van de Velde both closed with rounds of 2-under 71 to end at 11- under-par 173. Van de Velde finished with a bogey on the 72nd hole, after his tee shot found water, to force the extra session.
'What a day, what a week,' said Van de Velde. 'It was fun playing against Jean-Francois. He is a tough competitor. He played really well. He made a little mistake on 17, but I made equally on 18.'
The duo returned to the par-5 18th tee for the playoff. Both players found the fairway off the tee, but the pressure then got to each man.
Van de Velde's second shot flew long, left of the green and bounced into the water. Remesy, with an obvious opening, mis-hit his second shot and found the water short of the green.
Remesy took his drop and pitched his third 10 feet. Van de Velde, meanwhile, dropped where his ball went into the water instead of in the drop zone that Remesy played from.
Van de Velde pitched his fourth into a greenside bunker and the ball plugged in the sand. He blasted out into the rough. Van de Velde played his sixth inside of Remesy, but wouldn't need to putt.
Remesy two-putted for double bogey from 12 feet to become the first repeat winner since Nick Faldo in 1988-89.
'This is completely different to last year,' said Remesy. 'It is a shame for Jean as he also deserved the title, but I am very pleased to win it. Two times in a row is incredible. The playoff we were both exhausted and it was difficult to really finish that.'
The final round was completed Sunday despite a weather delay of nearly four hours. A strong thunderstorm brought drenching rain to the Albatross Course at Le Golf National.
Soren Hansen moved into a tie for the lead late on his opening nine, but faltered down the stretch to shoot even-par 71. He ended alone in third place at 8-under-par 276.
Frenchmen Francois Delamontagne and Gregory Havret shared fourth place at 5-under-par 279. They were joined there by Englishman Richard Finch and Australian Peter O'Malley.
Remesy was steady throughout his round. He opened with a birdie on the par- 3 second to get to 10 under.
The 41-year-old then birdied the sixth and made the turn at minus-12 after a birdie on the ninth. Remesy parred his next seven holes. He stumbled to a bogey on the 17th before a par at the last.
Van de Velde, well known for his late collapse at the 1999 British Open, birdied the first. He made it two in a row as he holed out from a greenside bunker on the second.
The 39-year-old bogeyed the par-4 seventh for the second straight round to fall back to minus-11. Van de Velde atoned for the mistake with a birdie on the ninth.
Van de Velde ran in birdie putts on 12 and 14 to get to 13 under and take a one-shot lead. He missed the green at the par-3 16th and was unable to get up and down for his par.
The Frenchman drove into the water on the 18th. He took his drop and found the putting surface with his third. Van de Velde was unable to make his par-saving putt though. The bogey dropped him to 11 under and back to the 18th tee for the playoff.
Van de Velde, playing this week on a sponsor's invitation, has missed most of the last two years after a pair of knee surgeries.
'I had a good chance and couldn't close it out, but I am pretty tough with myself,' Van de Velde said. 'I have to look at it a different way. I haven't been in this position the last three years and haven't been able to play golf the last two, so at least I am playing well, and all I can hope is to have another chance pretty soon.'
Bradley Dredge closed with a 3-under 68 to end in a tie for eighth place at 4-under-par 280. He was joined there by Anders Hansen, Jonathan Lomas, Jose Maria Olazabal and Eduardo Romero. Romero, who shared the lead entering the final round with Van de Velde and Remesy, struggled to a final-round, 5-over 76.