The ship, operated by France's Brittany Ferries, raised the alarm around 4:00 am (0200 GMT) when a fire was detected in one of the two engine rooms as it was off the coast of northwest France.
“The fire was quickly brought under control and there were no injured among the 766 passengers and 142 crew,” the regional maritime authorities said.
A French navy helicopter carrying firefighters and experts was dispatched to the vessel which was travelling from the southern English port of Plymouth to Santander in northern Spain.
— Voytenko Mikhail (@Maritime_Bullet) April 29, 2019
On board were travellers from Britain, France, Spain, the United States, China and Poland.
The MV Pont-Aven, which can carry up to 2,400 passengers and 650 cars, is the largest vessel in the company's fleet, measuring 184 metres (603 foot) in length.
It is particularly popular with Brits travelling to Spain with their dogs as it provides on-board kennelling..
It will dock at Brest port in the northwestern Brittany region later on Monday for checks.