The US National Security Agency (NSA) spied on French Presidents Jacques Chirac, Nicolas Sarkozy and Francois Hollande in 2006-12, Wikileaks says, the BBC reports.
The whistleblower website cites “top secret intelligence reports and technical documents” from the NSA.
A French official said spying “between allies was unacceptable”. Mr Hollande is to discuss the issue with security chiefs.
The US would not confirm the veracity of the documents.
In 2013 the NSA was accused of spying on German Chancellor Angela Merkel.
On Tuesday, Wikileaks said it began publishing the files under the heading “Espionnage Elysee” – a reference to the French presidential palace.
It said the secret files “derive from directly targeted NSA surveillance of the communications” of the three French presidents as well as French ministers and the ambassador to the US.