An airport spokesman said: “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.”
As a result of Ryanair's decision, one aircraft and five routes (Berlin, Derry, Lisbon, Riga and Sofia) will switch to Edinburgh Airport from November 2018.
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.
"As a result, we will transfer our Glasgow International based aircraft to Edinburgh in November where we will offer 11 new low fare routes (45 in total including London Stansted) and deliver over 3.5m passengers per annum at Edinburgh Airport."