Raed Abubadawia, 41, was released shortly before he was due to face an Israeli military tribunal on Tuesday, an anonymous source told the AFP news agency.
It was not known on Wednesday whether the charges against him had been dropped or why his hearing was scrapped.
Abubadawia was arrested on 21 September and accused of sheltering a Hamas sympathiser in his classes at Al-Najah University in the West Bank city of Nablus, according to his ex-wife, Nasrine Akhes, who lives in France.
AFP reports that the Israelis suspected him of propagating Hamas’s ideas among his students.
Following the kidnapping and subsequent murder of three Israeli teenagers, Israel arrested some 400 West Bank Palestinians and launched an offensive against the Gaza Strip, which is controlled by Hamas.
Abubadawia was awarded a degree at Paris’s Centre for Diplomatic and Strategic Studies and had three children with his first wife before moving to the West Bank and marrying again.
A campaign for his release was launched in France and the French consul met him after his release.
“This is proof that when people mobilise things get done,” Nasrine Akhes told the Courrier de l’Atlas magazine. “Raed is free but we shouldn’t forget the 7,000 other Palestinian prisoners.”