Just 13 days after delivering the world's biggest cruise ship to Royal Caribbean Cruises Ltd, STX France has signed a deal with the US-based company for one more ship of the same Oasis class and two slightly smaller Edge class boats.
"So we have an order book that is very full until 2023 and full until 2026," STX France CEO Laurent Castaing said on Thursday.
The Oasis class ship is the fifth of its kind - at 362 metres long and 66 metres wide.
Harmony of the Seas was the fourth and the fifth is currently being built at STX's Saint Nazaire shipyard.
The company has received nine orders this year, having announced deals with Italian-Swiss company MSC February and April.
Economy Minister Emmanuel Macron welcomed the news, pointing out that the shipyard had faced difficulty recently and unions had signed a competitivity agreement with management.
Cruise ships big polluters
While the orders are good news for jobs, they may be less good news for the environment, another concern of the French government in the light of last year's Cop21 climate conference in Paris.
Marine pollution analysts say that such large ships probably burn at least 150 tonnes of fuel a day and emit more sulphur than several million cars, according to the Guardian newspaper.