It was one of the largest emergency operations in recent months as calm seas drew a rush of migrants in small boats toward the coast of Britain.
The migrants were taken ashore at the port of Boulogne, where rescue workers said about 30 people had to be plucked out of the cold water as they rushed to climb aboard a French rescue vessel from a rubber dinghy that was taking on water.
The rescue took place about one nautical mile inside British territorial water, officials said.
Afghan, Indian, Iranian and Pakistani nationals were aboard the dinghy, which left the French coast in the early hours, the refugees said.
At the quayside, the migrants were handed fresh clothing and heat-retaining blankets by emergency workers.
French police earlier on Tuesday stopped almost 50 migrants trying to cross the Channel to Britain after mild weather and calm waters led a growing number of people to undertake the dangerous journey in recent days.
Migrant children rescued in French waters - in pictures
Guy Allemand, Mayor of the small village of Sangatte near Calais, said some migrants had been forced by police to turn back, but another 100 made it to the open water.
Migrant trafficking networks had recently changed their methods, Mr Allemand told Reuters.
"They now arrive with 'taxi boats' and the refugees are being asked to run into the water to catch them … rather than launching their own boats from the beach," he said.
Does the UK have a migrant crisis? - video
So far this year more than 40,000 people have crossed the Channel to Britain in small boats, up from 28,526 in 2021. Unusually mild November weather led to a rise in departures.
This month, Britain and France signed an agreement worth €72.2 million ($74.5 million) over the coming year to increase joint efforts to prevent illegal migrants making perilous journeys across the Channel.