Warner celebrated his 33rd B'day in style by notching up an unbeaten 100 from 56 balls and helping his side post an imposing 233-run total against Sri Lanka, Australia's fourth-highest score in T20 cricket.
Warner was lent good support from Captain Aaron Finch (64 from 36 balls) and Glenn Maxwell (62 from 28), who cracked half-centuries in the opening match of the three-game series.
Warner reached his ton from the last ball of the innings, in a knock featuring 10 fours and four sixes, surpassing his previous best T20 international score of 90 not out.
The opening pair reached their half-centuries in the same over, both by smacking consecutive sixes from hapless quick Kasun Rajitha who finished with messy figures of 0-75 from four overs.
Finch, whose knock featured eight fours and three sixes, was caught at deep midwicket in the next over from left-arm wrist spinner Lakshan Sandakan (1-41 from four overs).
Maxwell joined Warner and the pair put on 107 runs - their century stand took only 52 balls.