Ledger was born in Perth, Australia of Irish and Scottish descent. He lived in Western Australia until he was 16, when he left school (Guildford Grammar), a year early. He then moved to Sydney with his best friend, Trevor DiCarlo, in pursuit of a career in acting. Somewhat ironically, Ledger got his break in a TV series made in Perth, (1996), playing the part of a gay elite cyclist. Although the series failed to have much of an impact, he then starred in a US television series .

Ledger had a successful year in 2001, with his ShoWest Award for the Male Star of Tomorrow based on his performance in . In 2003, Ledger was named one of Australian GQ's Men of the Year for acting.

In 2005, Ledger received a "Best Actor in a Drama" Golden Globe nomination for his acclaimed performance in , in which he plays Wyoming ranch hand Ennis Del Mar, who has a love affair with aspiring rodeo rider Jack Twist, played by Jake Gyllenhaal. In the Both Mr. Ledger and Mr. Gyllenhaal make this anguished love story physically palpable. Mr. Ledger magically and mysteriously disappears beneath the skin of his lean, sinewy character. It is a great screen performance, as good as the best of Marlon Brando and Sean Penn.Ledger's magnificent performance is an acting miracle. He seems to tear it from his insides. Ledger doesn't just know how Ennis moves, speaks and listens; he knows how he breathes. To see him inhale the scent of a shirt hanging in Jack's closet is to take measure of the pain of love lost. from both the New York Film Critics Circle and the San Francisco Film Critics Circle. He was also nominated for an Academy Award for "Best Actor" for his performance.

Ledger has a turbulent relationship with elements of the news media, particularly paparazzi photographers. It's alleged that he spat at and assaulted a photographer in Sydney in 2004, while a relative also is alleged to have spat on a photographer in 2005. On Friday January 13 2006, several photographers retaliated, squirting Ledger with water pistols as he walked the red carpet for the Sydney premiere of

Ledger has more recently been subject to critical commentary and analysis in the press following his performance on stage at the 2005 Screen Actors Guild Awards. Ledger was seen giggling and his behaviour was decribed as odd when presenting Brokeback Mountain as a nominee for Performance by a Cast in a Motion Picture. The to the explain his actions were a result of stage fright given that he was ill-prepared to present the nomination, only being aware of his role minutes beforehand. "I am so sorry and I apologise for my nervousness," Ledger told the newspaperspan

Ledger met his former girlfriend Naomi Watts in 2002 during the filming of . They started dating in August 2002. The couple ended their relationship in April 2004.

Ledger is engaged to actress Michelle Williams, whom he met on the set of . They have a daughter, Matilda Rose, who was born on October 28, 2005. He is also a good friend of New Zealand actor Martin Henderson.

As of February 2006, Ledger currently resides in Brooklyn, New York, Los Angeles, California and Sydney, Australiaspan . Ledger is currently selling his Australian residence in Bronte, New South Wales for A$7.5 millionspan