|Date of birth||24 March 1990|
|Place of birth||Champigny-sur-Marne, France|
|Height||1.80 m (5 ft 11 in)|
|* Senior club appearances and goals counted for the domestic league only and correct as of 31 January 2012.
† Appearances (Goals).
Ketkeophomphone began with Racing Club de France, but joined 2006 the INF Clairefontaine football school. After one year, he left the club to sign for RC Strasbourg. In summer 2008, he was promoted to the reserve team. He made his debut against SC Bastia on 1 December 2009 in the National playing 44 minutes.
On 20 May 2011, he signed a five-year contract with Swiss Super League side FC Sion. On 31 January 2012, Ketkeophomphone and Sion mutually agreed to terminate the player's contract. The player subsequently returned to France to sign a four-year deal with Tours.
- Billy Ketkeophomphone Racing Club de Strasbourg
- Billy KETKEOPHOMPHONE - Racing Club de Strasbourg - racingstub.com
- Racing club de Strasbourg - Billy Ketkeophomphone
- Strasbourg - Bastia : Les groupes
- La fiche de Billy Ketkeophomphone. Football - L'Equipe.fr
- "Ketkeophomphone à Tours". SoFoot (in French). 31 January 2012. Retrieved 31 January 2012.