The song, "Echo: You & I", was recorded by the Indonesian-born singer Anggun, who was chosen by French television executives in November.
The Eurovision Song Contest will take place in the Azerbaijan capital of Baku on May 26th. Unlike some countries, France does not run a competition with public voting to choose its entry, preferring instead to make the choice behind closed doors.
The extract of the song was available on the amazon.fr website on Thursday, although it seemed to have been removed on Friday morning.
Several newspaper websites carried other links to the song, including Le Figaro.
The song was produced by Veronica Ferraro, who works with France's internationally known DJ David Guetta.
The upbeat track marks a change of direction for France, which last year entered a classical opera singer.
"I really wanted to do a show à l'américaine," Anggun is reported to have said.
The song will be in French and English, also a change of direction for a country which likes to protect music sung in its native tongue.
The full song will be available on the website of France 3 on Sunday at 4pm.