Academics from the business schools at Glasgow and Edinburgh universities found groups of angels investors had played a key role in ensuring that wealth amassed in Scotland was used to support potential high-growth firms in the country.
"In the absence of angel groups, this capital would likely be invested with traditional fund managers, with no assurance that it would fund entrepreneurial businesses in Scotland," said Professor Richard Harrison of Edinburgh University.
Suggesting Scotland has been punching above its weight in terms of angel investment, he said groups helped overcome the potentially small scale of the market resulting from a historic low level of entrepreneurial activity in the country.
The report, co-authored by Professor Colin Mason and Tiago Botelho of Glasgow University, found groups organised around experienced angels helped to attract funds from a wider range of people with money to invest.
The authors concluded Scotland had enjoyed a "particularly significant" growth in angel groups over the past decade.
In 2002, there were just two groups in Scotland, with about 70 members.
The LINC Scotland trade organisation works with 19 angel groups with a combined membership of just under 1000 angel investors.
Groups in Scotland provided a total of £22.5 million to companies in 2012, compared with £6m in 2002. They have harnessed Government funding to increase their firepower through the Scottish Co-Investment Fund.
The study found angels are filling the funding gap for firms seeking up to around £1m funding which was partly caused by the contraction of the venture capital industry.
However, Professor Mason, cautioned: "There is a new gap emerging for businesses that need further rounds of growth funding in excess of £1m."
He said the bank-supported Business Growth Fund may help to meet demand but suggested angel groups might also consider recruiting other co-investors and working with crowd funding platforms.
The study found more evidence the effectiveness of angels could be increased by their working in groups than suggested they would be better working alone.
The advantages for angels include better deal flow. Entrepreneurs could use groups to access a pool of wealthy, experienced backers.