"Democracy means accepting and allowing the confrontation of ideas," RTL radio wrote in a statement, adding that it would never let its editorial decisions to be dictated by others "whatever pressures it may face".
Zemmour currently appears twice weekly on an RTL current affairs programme and has been working with the station since 2010.
The announcement comes after television news channel iTele said it would cancel a show Zemmour appears on as a commentator following the controversy stirred up by his statements to an Italian newspaper.
In an interview with Corriere della Sera he said Muslims "kept to themselves in the suburbs" and the "French were forced to move out."
The remarks drew condemnation from civil rights groups, but Zemmour's forced exit from iTele was also criticised, with Marine Le Pen, the head of the far-right National Front party, calling it "censorship".
Zemmour was convicted in 2011 for inciting racial hatred after saying "most traffickers are blacks and Arabs".