Before the press screening of the film in competition "Redoubtable", a bomb alert prevented the festival-goers from going into the Palais, and security persons ordered to evacuate the building, Xinhua reported.
Squads of police were seen going inside the building with sniffer dogs. The alert was lifted about 20 minutes later. The entrance began getting back to normal.
The Cannes Film Festival has been put under heavy security following a spate of terror attacks across Europe. More than 500 surveillance cameras have been installed and up to 400 huge flower pots have been set along the Croisette as a barrier against any emergency.
The 70th Cannes Film Festival runs from May 17 to 28.