The summiteers will discuss adopting an action plan to help both countries succeed in their path to democracy.
Last month, the French government pledged 350 million euros in aid over the next year to Tunisia.
But Paris has adopted a firm policy towards the recent wave of Tunisians trying to enter France from Italy.
Fillon said last week that there was no longer any reason to give political asylum to Tunisians, because their country was "on the way to becoming a democracy".
Béji Caïd Essebsi's government has just reimposed a curfew in Tunisia, after several days of unrest, amid fears that the elections planned for 24 July will not go ahead.
Caïd Essebsi has hinted that the parliamentary elections might be postponed.
He said the process of electing an assembly to draw up a new constitution was very lengthy, and that parliamentary elections could not be held until that process had been completed.