The number of donors to higher education institutions north of the Border in 2012/13 was almost 22,850, up 15% on the previous year.
The number of donations from alumni rose to some 17,300, an increase of 20% on 2011/12.
Overall, Scottish universities were gifted some £40 million, which was similar to the previous year, according to a survey.
The poll, by fundraising organisation the Ross Group and the Council for Advancement and Support of Education (CASE), found the two largest donations were to St Andrews University, Fife, and Glasgow University.
While it is routine in America for former students to give money after they have graduated in recognition of the benefits of their education, the practice is far less popular in the UK.
Leading Scottish universities such as Aberdeen, St Andrews and Edinburgh have all embarked on major international campaigns to raise money through donations in recent years, but the money generated is still far less than that received through public means.
Philanthropic donations are often given in support of specific projects, such as author JK Rowling's donation to a Regenerative Neurology Clinic at Edinburgh University and Ann Gloag's donation to a Glasgow Caledonian University foundation supporting female entrepreneurs from disadvantaged communities.
Fran Shepherd, vice-president of international development at Glasgow University and a member of the Ross-CASE board, said: "These findings present an encouraging picture for the sector in Scotland, particularly the increase in donors.
"This shows more and more people, and not just those with a university education, are being convinced of the huge contribution of universities to society."
Kate Hunter, executive director of Case Europe, added: "It is hugely encouraging to see a continued increase in the number of donors giving to Scottish universities in 2012/13.
"Organisations and individuals are giving, in growing numbers, to support the work of universities across teaching, learning and research.
"Universities deliver benefit to the public in many ways and fundraisers are becoming increasingly professional and persuasive in making their case to a range of supporters."
Alastair Sim, director of Universities Scotland, which represents university principals, said the country's higher education institutions were becoming increasingly successful in diversifying the sources from which they generate income.
He said: "This is undoubtedly helpful, but it can never be a replacement for public investment.
"What is particularly welcome from this report is the increasing number of alumni wanting to give something back to their institutions because this is a culture Scotland is still developing, in contrast to America, where alumni giving is worth billions."