The mosque, in the southern French department of Hérault, was ordered closed after a raid uncovered leaflets promoting hate.
The Sète mosque, located on Rue de la Révolution, was ordered to be shut down on Wednesday until further notice.
A police raid had uncovered leaflets considered to be containing hate speech.
Interior Minister Matthias Fekl said the “head of the mosque was preaching a radical ideology that called for discrimination, hatred, and animosity towards others”.
The Ministry added that the mosque was “a regular meeting place worshippers with radical connections”.
Since the Paris attacks in 2015 the French government has been under pressure to take a hard line against radical preachers.
Authorities are making use of special powers as part of an official state of emergency in place since the November 13th attacks, and have been quick to close any kind of premises making calls for violence or glorifying terrorism.
One of the mosques was the Al-Islah mosque in Villiers-sur-Marne where authorities discovered a hidden Islamic school in the summer.
It was known to intelligence services because it was frequented by 12 individuals convicted of trying to travel to Syria to wage jihad.