Billy Osman Mehmet (born 3 January 1984) is a professional footballer and the current captain of Alsancak Yeşilova SK in the KTFF Süper Lig, where he plays as a striker.

Mehmet's football journey took him to Southeast Asia when he was acquired by the Thai Premier League side Bangkok Glass for an undisclosed fee.

As a youngster Mehmet was offered deals with Norwich, Arsenal, Millwall and Crystal Palace but decided to stay with West Ham United.

[citation needed] On 7 March 2009, Mehmet scored the only goal in a 1–0 win at St Mirren Park, converting a penalty to knock Celtic out of the Scottish Cup, and sending the Paisley club into the semi-finals of the tournament.

[7] The victory came after St Mirren lost 7–0 to Celtic in the Scottish Premier League meeting at Parkhead the week before.

[9] On 10 May 2010, it was confirmed that Mehmet had signed for Turkish side Gençlerbirliği on a two-year deal with a one-year option to extend his stay.

[10] However, in February 2011 Mehmet mutually agreed to terminate his contract with Gençlerbirliği due to financial issues affecting the club.

[16] On 18 January 2013, Mehmet terminated his contract with Perth Glory in the A-League after agreeing to sign with Thai Premier League side Bangkok Glass.

Billy Mehmet scored in his first pre-season match for Bangkok Glass vs Singapore Armed Forces in a 3–1 victory at the Leo Stadium.

[23] Mehmet decided to move onto Malaysian Super League side Sarawak FA at the end of the 2014 season.

After leaving Sarawak FA at the end of his contract, Mehmet signed for Tampines Rovers in the S-League after declining offers from football clubs in Malaysia and Indonesia.

[27] On 6 July 2017, Mehmet signed a contract with Turkish Cypriot club Merit Alsancak Yeşilova [tr].

Mehmet received a call-up from the Northern Cyprus national team ahead of the 2018 ConIFA World Football Cup.