"We must make sure, with the Iraqi authorities, that we find the means to have a judicial system that could try all these fighters, including the French ones," Le Drian told BFMTV news channel.
"Our concern is that security is no longer assured and that the Kurds are abandoning these camps.
This is a major danger.
This is why I am going to Iraq soon," he said.
Dozens of French IS fighters and hundreds of French women and children are being held by Kurdish groups in areas close to the Turkish offensive.
France fears they could escape amid the strike, return home and carry out attacks.
"To my knowledge, the Turkish offensive and the positioning of the SDF (Syrian Democratic Forces) have not so far threatened the safety and security of these camps.
Currently, jihadist prison camps are still held by the Kurds," Le Drian said.
France has repeatedly expressed a preference for its citizens held in Iraq and Syria and who fought with the Islamic State to be prosecuted there, fearing growing militancy at home.
In coordination with six other European countries -- the United Kingdom, Belgium, Germany, the Netherlands, Sweden and Denmark -- France has been working for the establishment of an international court in Iraq.
Some 12,000 fighters, including Syrians and Iraqis, as well as about 3,000 foreigners from 54 countries are detained in Kurdish jails, local media said citing official Kurdish data.