The decision, which is said to affect at least 300 jobs, is being blamed by Ryanair on the cost of Air Passenger Duty and means Ryanair will only fly from the airport to Dublin, Wroclaw and Krakow.
One aircraft and five routes - Derry, Lisbon, Sofia, Riga and Berlin - will switch from Glasgow to Edinburgh Airport.
Ryanair claims Edinburgh “has a stronger inbound component” than Glasgow. Next summer, Edinburgh will offer 45 Ryanair routes including new services to Gothenburg, Hamburg, Memmingen, Stockholm Skavsta, Seville and Tallinn.
At a press conference, Ryanair said the decision could see 500,000 fewer passengers at Glasgow, where it opened its base in 2014.
Ryanair’s chief commercial officer David O’Brien said: “Ryanair regrets these cuts in the weaker Glasgow market where efforts to stimulate low fare demand are severely hampered by the continuing burden of APD.”
The decision was slammed by a Glasgow airport spokesman who added: “We are bitterly disappointed at this decision by Ryanair which is not only damaging for Glasgow and wider Scottish connectivity, it will impact approximately 100 jobs locally.
"This is a result of the airline’s review of its single aircraft bases, however, we have been left in no doubt it is also a consequence of the Scottish Government’s inability to introduce its proposed 50% cut in Air Departure Tax (ADT).
“Despite clear and repeated warnings from both airports and airlines about the potential impact of this policy not being implemented, we are now faced with a stark scenario that includes the loss of 20 services and a significant number of jobs.
“This is the second example in as many months of an airline cutting capacity in Scotland because of the lack of movement on ADT.
"The reality is this capacity will be reallocated elsewhere in Europe to countries with more favourable aviation taxation policies to Scotland’s detriment.
"We cannot sit back and risk Scotland’s connectivity being further eroded. It is imperative there is immediate action on ADT.”
