Jenni teaches at a school in LyonAlexis Jenni received the Prix Goncourt for his debut, L'Art Francais De La Guerre (The French Art of War).
As is traditional, the 10 Euro (£8.60) prize was handed out at the Drouant restaurant in Paris. The prize virtually guarantees high book sales.
Past recipients include Marcel Proust in 1919 and last year's controversial winner, Michel Houellebecq.
Houellebecq, who is known for his frank depictions of sexuality and alienation, has long polarised critical opinion in his home country, with some accusing him of obscenity and misogyny.
Last year, he won the prize for La Carte et le Territoire - The Map and the Territory - in which a fictional representation of the author is murdered.
The Goncourt prize, which was first handed out in 1903, is presented annually to the author of "the best and most imaginative prose work of the year".
Jenni, 48, is a biology teacher at a high school, Saint-Marc, in Lyon and has three children.
According to a profile in France's Le Monde newspaper, he has written two other novels - one which was rejected by editors, and one which he never submitted.
His novel explores France's conflicts in Algeria and South East Asia, and uses those experiences to examine the country's current attitudes to race and immigration.