The new routes will serve Bordeaux, Gothenburg, Marrakech, Marseille, Nantes and Thessaloniki.
The schedule of 63 routes in total will include more flights to Belfast and 4,000 on-site jobs per year, Ryanair said.
Julian Carr, aviation director for Manchester airport, said: “It’s fantastic to see Ryanair adding yet more routes and continuing to grow from Manchester.
“Gothenburg and Marseilles are currently unserved from the airport and along with their other new routes will offer our 27.9 million passengers an even greater choice of destinations, whether it’s for business or leisure.”