At one stage the Lions trailed by 26 points but they dominated the final quarter to win 21.10.136 to 18.7.115.
Following on from their win against Collingwood at the MCG in round 15, the Lions have now firmly buried their Melbourne hoodoo.
The Lions' efficiency was best summed up tonight by Daniel Bradshaw and Tim Notting, who between them had 10 kicks for the game yet between them finished with ten goals with Bradshaw fittingly sealing the game with his sixth goal at the 23-minute mark of the final term.
The victory consolidated Brisbane in second place, behind reigning premiers Essendon, and with three of their last five games to come at the Gabba plus an away game against bottom side Fremantle, the Lions should stay there.
That would not only give them the "double chance" in September but would give them the chance of reaching their first ever grand final without having to play a final in Melbourne.
But on the evidence of the past two weeks, playing finals in Melbourne may no longer worry Brisbane even though the Lions have never won a final in Melbourne.
With Jason Akermanis, Simon Black and skipper Michael Voss dominant in midfield, the Lions finished all over the team that has been their toughest opponent in recent years.
While the Lions now set their aim on their highest ever finish to a home and away season, the Roos' finals hopes are in jeopardy.
The Roos have never missed the finals since Denis Pagan took over as coach in 1993 but now find themselves a game out of the eight plus percentage with only five matches remaining.
And while the Roos' attack remains as potent as ever with Sav Rocca brilliant tonight with six goals and skipper Wayne Carey, Corey McKernan and Byron Pickett all constant dangers, their defence is in tatters.
After conceding 27 goals against Essendon last week after letting slip a 69-point lead, the Roos' defence again leaked more than 20 goals tonight.
While Jason McCartney was gallant at centre half back, the remainder of the Roos' backline looked too small and too slow against Brisbane's multi-pronged attack.
The Roos now must win at least four of their last five games to make the finals but they face a tough task next week against fellow top eight contender Sydney, at the SCG.
Scoreboard:
BRISBANE LIONS: 5.1, 9.2, 15.10, 21.10 (136)
KANGAROOS: 5.2, 11.4, 16.5, 18.7 (115)
Goals: Brisbane: D Bradshaw 6 T Notting 4 C McRae 4 L Power 2 N Lappin 2 B Scott J Akermanis J Brown. Kangaroos: S Rocca 6 C McKernan 4 W Carey 3 B Pickett 2 B Harvey 2 L Harding.
Best: Brisbane: J Akermanis M Voss D Bradshaw S Black T Notting C McRae. Kangaroos: S Rocca B Harvey B Pickett M Burton J McCartney C McKernan.
Injuries: Brisbane: C Bolton (omitted) replaced in selected side by M Kennedy. Kangaroos: L Colbert (knee) replaced in selected side by L Harding, C McKernan (knee).
Reports: Nil.
Umpires: K Nicholls, B Sheehan, M Ellis.
Official crowd: 26,776 at Colonial Stadium.