The budget airline said its existing once daily flight from Prestwick to Dublin will now switch to Glasgow as part of an expanded three times daily business service between Glasgow and Dublin.
It will also create a new base at Glasgow, Ryanair's 69th in total, with a new route between the city and London Stansted, and will add another new route three times a day between Edinburgh and London Stansted as Ryanair invests over £360m in Scotland.
However, it said it remains committed to its long-standing base at Prestwick, where the airline has a maintenance facility, and said it was currently in discussion with the Scottish Government to explore growth opportunities to/from Prestwick.
Ryanair celebrated its Scottish growth and new business routes by releasing 100,000 seats for sale across its European network, at prices from £19.99 for travel in August, September and October. These low fare seats are available for booking until midnight on Monday 7 July.
Ryanair's new Scottish routes, which start in October, go on sale on the Ryanair website tomorrow at fares from just £19.99, which the airline said were almost half of BA's and 40% cheaper than Easyjet's.
Chief commercial officer David O'Brien said: "Ryanair is pleased to launch three new Scottish routes, between Edinburgh and London, Glasgow and London, and Glasgow and Dublin, starting this October...in response to strong demand for Ryanair's low fares from Scottish consumers and business customers, and increased competition between Scottish airports.
"Ryanair will also open a new base at Glasgow International this winter, and will deliver more than 500,000 new customers through Scottish airports this year.
"Scottish consumers already choose Ryanair for our low fares, industry leading customer service and great route choice. However, Scotland cannot fulfil its true tourism potential until Air Passenger Duty is removed and we would urge Scotland to follow the example of Ireland, where Ryanair has launched 21 new routes and will deliver over 1.2m new customers this year, in response to the Irish Government's welcome decision to scrap APD. Regardless of the outcome of the referendum, Scotland cannot unlock its full potential until APD is repealed."
The Scottish Government took the airport into public ownership last year for £1 after owners Infratil earmarked it for closure.
Deputy First Minister Nicola Sturgeon has announced a £7 million investment for repairs and improvements, but said it could be a long time before taxpayers see a return on the investment.
Adam Ingram, SNP MSP for Carrick, Cumnock and Doon Valley, said: "I welcome Ryanair's commitment not only to Prestwick Airport but to other Scottish airports with the launch of ten new direct routes by the end of the year - this will be an important boost for the Scottish economy.
"I also welcome the airline's confirmation that it is in discussions with the Scottish Government to explore growth opportunities to and from Prestwick. Ryanair has had a longstanding business relationship with Prestwick Airport and they will continue to do so.
"However, I agree with comments made by Ryanair that Air Passenger Duty (APD) is thwarting the potential growth in tourism across Scotland. Westminster had its chance to devolve APD to the Scottish Parliament and failed - the UK government actually rejected a key recommendation of the Calman Commission to do so. The only way to get this vital job-creating power is to vote Yes in September."
SNP MSP for South Scotland Chic Brodie added: "The Scottish Government has consistently made clear that there is a place for Prestwick Airport in the Scottish aviation market - this is welcome news as the airport is an important employer in the area, helping to support almost 2,000 jobs.
"One sure fire way of securing aviation jobs across Scotland is to scrap APD. With a Yes vote and the full powers of independence, we will cut APD with a view to abolishing it completely in the long term. This would boost tourism and give Scotland the opportunity to achieve our full tourism potential."