Opting to bat, Gayle literally butchered the Australian bowlers with a 41-ball 75-run innings as West Indies notched up 205 for four, which incidentally is the highest total of this edition.
The Caribbean team then returned to skittle out Australia for a paltry 131 with 3.2 overs to spare to set up a summit clash with Sri Lanka on Sunday.
Australian skipper George Bailey did put up a fight with a 29-ball 63, which was laced with six fours and four sixes but he was let down by the other batsmen, who returned to the pavilion without much to show.
Leg-break bowler Samuel Badree (2/27) removed openers David Warner (1) and Shane Watson (7) in his first three overs, while Marlon Samuels got rid of Mike Hussey (18) as Australia were tottering at 42 for three after the six overs of Powerplay ended.
In Image: West Indies' cricketer Chris Gayle, center, dances with teammates to celebrate their win over Australia