The Tribunal des affaires de sécurité sociale (Social Security Affairs Court) in the eastern town of Lons-le-Saunier in the Jura region ruled that the Pelizzari group had committed an "inexcusable error" by failing to protect Serge Personeni from a work hazard.
The 49-year-old was quoted by French daily Le Figaro as saying: "Working in a piggery means listening to constant noise and screams from the pigs, eight hours a day, seven days a week."
Personeni was in charge of feeding and looking after nearly 4,000 pigs when he worked there from September 2001 until February 2008.
Deafness was recognized as a work hazard in France in 2012. It was then decided that those working in places with decibel levels higher than 85 should receive protective equipment.
When feeding, the pigs under Personeni's care made a noise which reached between 121 and 133 decibels, the court found, according to French daily Le Figaro.
The amount to be paid to Personeni will be decided later after he is inspected by a doctor.
During a hearing in June, the court said Personeni was made to "work in conditions incompatible with human dignity," according to regional daily Le Progrès.