Dusko Tosic is a Serbian professional footballer who plays as a defender for Chinese club Guangzhou R&F in the Chinese Super League.

Tosic began his career in his native Serbia playing for OFK Beograd before moving to French club Sochaux for the 2006–07 season. He transferred to Werder Bremen for the 2007–08 season, where he signed a contract until 2011. On 1 February 2010, his contract with Bremen was dissolved. Tosic signed for Portsmouth on 12 February 2010. He signed a loan deal to play for QPR until the end of the season on 25 March 2010. On 7 July 2010, he joined Red Star Belgrade, signing a three-year contract, rejecting the interest of some English clubs. On 31 August 2011, it was announced he would join Real Betis on a two-year loan with an option of Betis buying the player afterwards. He returned to Red Star on January 2012. On 2 June 2015, Tosic signed a three-year contract for Besiktas. Besiktas won the title in the Super Lig in 2015–16, as well as in 2016–17, with Tosic mainly occupying the left central defender position. In 2018, Tosic signed for Chinese side Guangzhou R&F.

Tosic made his national debut against Norway on 15 November 2006, a friendly which ended in a 1–1 draw, and has gone on to earn over 22 caps.