The ex-France international began his career with Metz before success with Fulham saw him earn a £12.8 million move to Man Utd in 2004, where he would go on to win two Premier League titles and a Champions League crown.
Stints at Everton, Tottenham and Sunderland followed after injuries marred his spell at Old Trafford and the Frenchman has now called time on his career after managing just six appearances for Lazio last season.
"I will stop to be call a professionnel (sic) footballer and wish many young talent to enjoy as much as me my football," Saha posted on his Twitter account.
"Want to thks (sic) all managers, all staffs ,all teammates, all opponents, all fans, for all support and love towards me during my football career.
"I'm a proud man but without you all I won't be myself now. Thx (sic) for the challenges thx for the help thx for the memories thx for the passion."
Saha appeared 20 times for his country and was a member of the Bleus squad that made it to the 2006 World Cup final in Germany.