Defending champion Wardley started the fight at pace with two knockdowns in the first three rounds - including his first in the opening 10 seconds of the bout - but Dubois' power was too much for Wardley as his dangerous right hook caused serious damage to his blood-covered opponent.
Dubois came close to a stoppage victory in the sixth round, leaving Wardley reeling on the ropes, but he sealed the deal in the 11th when a flurry of late punches forced referee Howard Foster to wave off the bout.
Fabio Wardley vs Daniel Dubois - as it happened Get Sky Sports or stream with no contract on NOWDownload the Sky Sports app for expert analysis, best video & more
"It was a war," Dubois said afterwards. "We came through the sticky moments. Thank you Fabio for that, thank you.
"What a great fight, what a great battle, man."
He continued: "We move on now. I want to grow from this fight, improve and go on and reign as champion again."
He finished by roaring: "Are you not entertained? What a fight, what a warrior, thank you!"
Promoter Frank Warren confirmed afterwards there was a rematch clause in the fight contract.
"These two guys showed such heart. Great heart. Chins. It was an amazing fight," Warren said. "Absorbing. It had everything, exciting. The best heavyweight fight I've ever put on."
Wardley vs Dubois: How it happened
Dubois entered the fight hoping to bounce back from a second stoppage defeat to triple world title holder Oleksandr Usyk, but his night got off to an all-too-familiar start when the boxer was reportedly stuck in traffic on the way to the venue - echoing his notorious late arrival before his loss to the Ukrainian due to a pre-fight party.
Wardley, however, couldn't have begun his night any faster as the defending champion knocked Dubois down with a huge right hook less than 10 seconds into the opening round.
Dubois, visibly agitated, got back into the fight, rushing towards Wardley in a clinch and subsequently landing two mammoth right hands to swing momentum in his favour.
The Londoner continued his recovery with a strong second round, landing a big arching right against Wardley on the ropes, but his opponent struck back with an extraordinary second knockdown in the third, leaving Dubois reeling on one knee and needing eight seconds to get up.
Miraculously, a fatigued Dubois battled back, landing a ferocious one-two before a clubbing right hook left Wardley on the back foot in round four. The Ipswich Town superfan has never been knocked down in his 20-fight, but even he looked unlikely to stay on his feet for long as Dubois landed numerous hooks and jabs to the head.
Wardley continued to flail, missing with his trademark right hand, and Dubois capitalised with a brilliant left jab to the face. He came close to a stoppage victory in the sixth when he landed a flurry of blows to his opponent, who was somehow still standing despite visible blood and serious damage.
But the defending champion demonstrated the resilience which has taken him from 'white collar' boxing to the top of the professional world when he landed a left jab to the face, leaving Dubois looking vulnerable for the first time in multiple rounds.
Still in the ascendancy, Dubois continued to land blow after blow but Wardley, with legs unsteady, would not buckle. He had a huge gash on his nose inspected, but the cut was not enough to stop the boxer from entering the ninth round.
The Londoner landed yet another brutal sweeping right hook to Wardley, who wobbled once again but stood tall and replied with an uppercut of his own.
Another inspection from the referee and his corner preceded the 10th round, yet Wardley would still not give in of his own accord. The resilient boxer could only stand so much, though, and Dubois' flurry of shots at the start of the 11th were deemed the final blows by referee Howard Foster, who called off the fight and ended Wardley's reign as WBO title holder.
A titanic contest
Sky Sports' John Dennen writes…
That was a contest of unadulterated savagery. When Daniel Dubois was dropped to the seat of his shorts after only seconds of the fight and a couple of right hands from Fabio Wardley, it looked like he would unravel.
Questions that had haunted him after his losses to Oleksandr Usyk and as far back as his first career defeat to Joe Joyce were suddenly set to be asked all over again.
If that visit to the canvas could be attributed to a flash knockdown, in the third round, when he sank to his knee after another heavy blow, old doubts voiced about his temperament then returned with vengeance.
But he rose, he regrouped and in doing so, without words, he found his reply. He answered Wardley, he fired back, at first wildly, then with precision and always with brutal power.
Having shown his fortitude, he began to dissect Wardley when he uncorked hard, firm, quick jabs, that damaged the champion.
Then the power of his heavy right hand took full effect.
In those early rounds Wardley had shown his physical qualities, his own explosive power and his instinct for an opening, despite the unorthodox background of his own journey from 'white collar' boxer to professional world champion.
But as Dubois began to dismantle him, Wardley had to rely on the grit that has been the hallmark of so many of his top-level performances. He took so many, too many, of Dubois' awesome power punches and yet doggedly refused to go down.
Wardley had shown, against Frazer Clarke, against Justis Huni and against Joseph Parker, that he is at his most dangerous when hurt. But that quality, that's won him so many admirers, kept him in this fight too long.
Round after round he was getting pummelled and the swollen eye and his cut and damaged nose where visible proof of that.
After the break to end the ninth round, his legs were still quivering and unsteady beneath him. Yet he was allowed to go on. He had to endure another round of punishment and a furious salvo from Dubois at the start of the 11th before finally the fight was ended.
There can be no doubt about Wardley's toughness and determination. And if Dubois had any doubts about himself going into this one, he found his own answers too.
