Italy scrum-half Lorenzo Casilio set the tone for a pulsating contest with a score inside five minutes but France were level by the midway point of the half thanks to Fabien Brau-Boirie.
Hot prospect Marco Scalabrin bulldozed over for his third try of the Championship to give Italy a half-time lead which was soon stretched after the interval via a Martino Pucciariello penalty.
Tries from Maxim Granell and a second from the towering Brau-Boirie looked to have broken Italian hearts but a Jacopo Botturi score and a seismic defensive effort at the last ensured they claimed their first win of this year’s Championship.
France handed the visitors the early momentum, infringing from their own kick-off to give fly-half Pucciariello the chance to boot downfield.
Italy continued their charge and scrum-half Casilio put the finishing touches to a brilliant opening drive, scorching the outside of the defence to dot down in the corner.
France were then on the board just minutes later, as Jean Cotarmanac’h bisected the posts to reduce the arrears.
While Italy had the upper-hand in the scrum, forcing three penalties inside the opening 17 minutes, the French backs were enjoying themselves too and scrum-half Lucas Zamora was a dropped ball away from a one-on-one with full-back Mirko Belloni.
The Azzurrini’s grunt work threatened to take the game away from the hosts, Pucciariello adding another three points after France vice-captain Noa Zinzen lost his bind at another destructive Italian scrum.
But France levelled within a minute. A fine blindside break coupled with a pinpoint inside pass from Brau-Boirie allowed Zamora to go over at the second time of asking and level the scores at 8-all.
Italy surrendered good territory on three separate occasions before the break as their lineout misfired, but they left the field with their noses in front thanks to the freakish strength of Scalabrin.
The young flyer, who likens himself to Duhan van der Merwe, powered over in the corner after a sensational through-the-legs pass from Belloni kept the move alive.
France had come within metres of a second score with the clock in the red but were held up just short of the whitewash, leaving Italy with a slim 13-8 half-time lead.
The second half started in similar fashion to the first, with referee Ian Kenny penalising France and on this occasion Italy opted for points, a call which Pucciariello repaid with three points.
Every time the men in white looked like pulling clear, France reeled them back in and a lightning finish from debutant wing Granell reduced the deficit to just three points.
Italy threatened to unravel with centre Nicola Bozzo sin-binned but were handed a reprieve on their own line with France penalised for crossing after a hasty lineout drive.
They failed to make the most of their numerical advantage but after sustained pressure found a breakthrough to claim the lead for the first time.
Outside centre Brau-Boirie ran an unstoppable line to dot down under the posts with Cotarmanac’h adding the extras to make it 20-16 inside the final quarter of the game.
Italy looked to be on the ropes but produced a brilliant counterpunch to regain the lead just 10 minutes from time. A penalty try seemed an inevitability after several collapsed scrums but No.8 Botturi burrowed over before Pucciariello converted to ensure it was a seven-point gain.
Back came France as the pendulum shifted again but they were held up inside Italy’s in-goal area. That looked to be that, but there was more drama to come as Italy replacement lock Giacomo Milano was pulled up for sealing off with just seconds to spare.
France headed for the corner but fluffed the lineout, leaving Italy to celebrate a memorable upset.
