The song will be called "Echo (You and I)", reported daily newspaper Le Parisien on Tuesday.
In a rare acknowledgement of the preference of most countries to sing in English, the song will be two-thirds French and one-third English.
Veronia Ferraro, who works with internationally-known French DJ David Guetta, will produce the track.
Unlike many countries, France decided to pick its entry for the 2012 song contest without a public vote.
Anggun was chosen behind closed-doors by state-owned television channel France 3 in November.
France is desperate to do better at the annual singing festival and hopes Anggun will help end the 35-year drought since the country last won the contest in 1977.
The contest takes place on May 26th in the Azerbaijan capital Baku. Anggun's entry is expected to be available by end March.