Namouchi was signed by Rangers in September 2003 on a free transfer from French team AS Cannes. He made his Rangers debut on 10 January 2004 against Hibernian as a substitute. At Rangers he picked up a Scottish Premier League winners' medal in 2005, and appeared in every game in their UEFA Champions League campaign where he was earmarked by Luis Figo as the player that "impressed him most".
Namouchi joined Lorient for a fee of £500,000 in August 2006 after being told by Rangers manager Paul Le Guen that he was surplus to requirements.
In late 2009, Namouchi agreed to a contract with the Turkish Süper Lig side Sivasspor after lengthy contract negotiations.
He is a Tunisian international, despite being born in France. He won his 14th international cap against Belarus in May 2006, scoring his first international goal in the same game. He was also a member of Tunisia's qualification for the 2006 FIFA World Cup and featured in all of their three games at the tournament.