Heskey has signed for the Newcastle Jets in Australia's A-League, saying: "This is an exciting new period in my life."
The former England, Aston Villa and Liverpool striker's signing was confirmed by Newcastle after the 34-year-old signed a deal for the 2012-2013 season which begins next month.
Capped 62 times by England, Heskey scored 110 goals in 516 games in the Premier League during a 17-year career in England.
Newcastle chief executive Robbie Middleby: "Emile has played our game at the highest level in England, both internationally and domestically, and he finished last season playing with Aston Villa in the English Premier League.
"We are aware that Emile had other offers but he is genuinely excited to be a part of what we want to achieve at the Jets.
"Emile's relationship with former English Premier League players Michael Bridges and Robbie Fowler assisted him in understanding what the A-League has to offer."