Batley fell behind on three occasions but fought back each time and when winger Johnny Campbell crossed in the left corner and Dave Scott added a towering touchline conversion it set up a pulsating finale.
A magnificent defensive performance set up Batley’s win as they repelled the Vikings attack, especially in the first half when they restricted them to just one try having played down the slope.
Batley were twice forced to drop out in the early stages of the game as Widnes piled on the pressure but the Vikings were unable to unlock a solid Bulldogs defence.
Batley responded well as Louis Jouffret was tackled close to the line following a jinking run before the Frenchman kicked right but the ball was gathered by a defender.
Batley were forced to drop out for a third time but again their magnificent defence denied Widnes before Jack Downs intercepted a pass and raced 30 metres up the slope to relieve the pressure.
It took Widnes 31 minutes to break the deadlock as a penalty put them on attack. Joseph Cahill was held by a terrific three-man tackle in front of the posts but the Vikings moved left and created space for Lloyd Roby to race through a gap and over for the opening score which Jack Owens converted.
Batley fought back immediately and deservedly levelled as Jouffret kicked left. Paul Brearley appeared to have knocked the ball on with the line at his mercy but Michael Ward pounced to plant it down and the try was awarded, with Scott converting to level.
Batley could have gone into half-time ahead as Ward drove the ball in and popped up a lovely pass but it was intercepted with Jouffret poised to pounce for the try.
Widnes put Batley under more pressure at the start of the second half with Jordan Johnstone held up over the line by more terrific defence before a kick to in-goal was palmed dead.
The pressure finally told as Widnes launched another attack on the back of the drop out and Johnstone collected a pass to storm through a gap for a try which Owens improved.
Batley were dealt a blow when Toby Everett was sin-binned for an infringement in a tackle but it was while the Bulldogs were down to 12 men that they hit back to level for a second time.
Back-to-back penalties but the Bulldogs on attack and having driven play close Joe Taira made a storming run to the line and managed to plant the ball down under a cluster of bodies, with Scott converting.
Widnes looked to have grabbed a crucial try after 57 minutes as they attacked on the back of a penalty and Roby showed a turn of pace to storm through a gap to score. Owens converted and the Vikings led by six points for a third time.
Despite fatigue setting in following their defensive efforts, Batley surged back down the slope.
A dangerous Jouffret kick was hacked dead and Widnes were forced to drop out for a second time in quick succession as Batley piled on the pressure.
Cahill was given a stern warning following an off the ball incident which left Bulldogs hooker Alistair Leak requiring treatment but it was on the back of that penalty which Batley scored again.
Brearley drove the ball in on the left edge and popped a lovely pass out for Jouffret, who sent Campbell in at the corner, with Scott landing a towering touchline goal to make it 18-18 with nine minutes left.
Owens was wide with a drop goal attempt with many of the Widnes supporters packed behind the posts ready to celebrate.
Batley then drove the ball downfield. They set up an excellent position for a drop goal attempt but interference at the play the ball on the last tackle gifted them a penalty in front of the posts and Scott slotted over the goal.
There was late drama as Batley were caught offside following a short Widnes kick off.
Owens went for goal to equalise but his tricky effort from 30 metres out sailed wide and Batley wound down the clock to seal a memorable win.
Batley Bulldogs: Scott; Reittie, Sneaton, Tomlinson, Campbell; Jouffret, Yates; Gledhill, Leak, Lillycrop, Downs, Bretherton, Manning. Subs: Everett, Taira, Ward, Brearley.
Widnes Vikings: Roby; Ince, Dean, Brand, Freeman; Owens, Lyons; Chaephow, Johnstone, Cahill, Walker, Hansen, Leuluai. Subs: Farnworth, Speakman, Walsh, Hatton.
Referee: Marcus Griffiths.