The new short-haul services include connections to Reykjavik, Paris, Agadir, Nantes, Gothenburg and Geneva.
The long-haul routes will provide direct links to Washington, Chicago, Los Angeles, Ethiopian capital Addis Ababa and Halifax in Canada.
Together they will make almost two million extra seats available, an 11% increase in capacity compared to last summer.
Vincent Harrison, Dublin Airport's managing director, said: "We are particularly pleased that Dublin will have a direct connection to sub Saharan Africa this summer, making it easier for our customers to access three continents – Africa, Europe and North America - with Ethiopian Airline’s new Addis Ababa-Dublin-Los Angeles route, as well as direct services to Europe, the Middle East and North America.
"Significant increases in seat capacity and frequency on 25 existing routes will give our customers greater flexibility and more options whether they are travelling for business or leisure purposes during this summer season," he added.
The airport is celebrating its 75th anniversary this year. Aer Lingus will also introduce a third daily Dublin-JFK service for the peak summer season.
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