The win rounds out a golden year for Junior Warriors coach Stacey Jones in his first year in charge and helps ease the pain of defeat for the players after going down to Penrith in last year's decider. His side defied history to become the first team to win the competition from eighth spot.
"We gave them a sniff and they came back into the game but full credit to my boys, we do the most travelling and we've been here five weeks straight," Lisone said. "We're taking the trophy back home where it belongs."
Both sides were denied early try scoring chances before the Junior Warriors capitalised on the first error of the match, when a good shot from Lino jolted the ball loose for Kata to collect their first try.
They quickly extended their lead when Kata scooped up Adam Tuimavave-Gerrard's short side grubber for his second but the kiwi outfit were forced to reshuffle their line-up when a head knock forced hooker Kurt Robinson from the field.
The arrival early in the second-quarter of Jayden Nikorima caught the tiring Junior Warriors forwards napping, when his dummy-half dart saw Alex Barr score under the bar before Ashley Taylor's goal narrowed the margin to four.
With halftime looming and momentum in the balance the Junior Warriors struck twice in four minutes, with a Lino cut-out pass finding Kata for his third, before makeshift hooker Nathaniel Roache split the defence to send Lolohea in for try number four.
That trend continued early in the second-half when quick hands from Lolohea and Abbey saw Maumalo cross and 10 minutes later it looked a done deal when Lino laid on a deft pass for prop Lisone to score their sixth.
However, with 25 minutes remaining the momentum swung when Byrnes scored his quick double to give his side hope but the Junior Warriors clung on to clinch the club's third Under 20s title following wins in 2010 and 2011.
Junior Warriors 34 (Solomone Kata 3, Tuimoala Lolohea, Ken Maumalo, Sam Lisone tries; Mason Lino 5 goals) Brisbane Broncos 32 (Alex Barr, Paul Byrnes 2, Kodi Nikorima, Jack Tuttle, Jayden Nikorima tries; Ashley Taylor