Triple J Hottest 100, 2009

The 2009 Triple J's Hottest 100 Volume 17, was announced on Australia Day 26 January 2010. It is the seventeenth countdown of the most popular songs of the year, as chosen by the listeners of Australian radio station Triple J.

Voting commenced on Boxing Day, 26 December 2009, and closed on 17 January 2010. 1.1 million votes were received, a record number.

Controversy began when it was rumoured that the winner had been unintentionally leaked by the ABC. The ABC Shop website promoted the February issue of Jmag with a description stating "Topping the 2009 countdown is Mumford & Sons' 'Little Lion Man'". Triple J neither confirmed nor denied the rumour with some even claiming it was a hoax, amounting to a clever marketing campaign. The leak led Sportingbet Australia to close all betting on the countdown. The leak proved to be accurate. For the first time, the number one song was performed live on air by the winning artist, Mumford & Sons, from Triple J studios, followed by the studio version of the song.

#101–#200 List
On 31 January 2010, Richard Kingsmill revealed the "second 100 songs" (#101–#200) list on his blog.

Top 20 Albums of 2009
Bold indicates winner. Sarah Blasko won the J Award for As Day Follows Night.

CD release
Triple J's Hottest 100 Volume 17 is the compilation featuring the best of the Top 100 voted tracks on two CDs.