Jean-Pierre Mignard, a member of the high authority in charge of organising the primaries confirmed this in an interview with Le Parisen newspaper on Sunday.
After sexual assault charges were brought against Strauss-Kahn in the United States, there was talk in the party of delaying the primary– as he was seen as a top contender.
But as charges were filed and the case moved forward, the party decided to keep to the dates.
The primary will be held on 9 October 2011. Six candidates are in the running, including Party Secretary Martine Aubry, former secretary Francois Hollande, former candidate Segolene Royal and three newcomers - MP Manuel Valls, Arnaud Montebourg, and Jean-Michel Baylet.
Baylet is not a socialist, but decided that running on the Radical left party would only hand votes to the far right.
Strauss-Kahn could conceivably still run as an independent. He would need to come up with 500 signatures to get on the ballot, and he has until 16 March 2012.