An ageing workforce, an increasing demand for skills, and a "climate of hostility" to immigration could harm the flow of skilled people coming into UK IT departments from abroad, the report said.
The Work Foundation said the availability of skilled workers influences location decisions made by multinational companies in knowledge-intensive industries such as financial services and high-tech manufacturing.
A purely native supply of labour would "limit" the UK and remove the competitive edge created by access to global high-skilled labour, it said.
The IT sector's skills council E-skills said the industry needs around 150,000 new recruits every year. In 2005, 167,000 highly skilled immigrants entered the UK across all sectors.
The Foundation says employers will need more immigrants with IT skills as they cannot rely on a steady home-grown supply of good quality candidates.
The UK IT sector employed 24.5% of highly skilled migrants in 2005, the largest proportion of any industry.
The report says the sector's heavy reliance on foreign workers means it will have to work hard to keep attracting them. The rising demand for staff will not be met by upskilling native workers.
"Being able to access high-skill labour from around the world creates a competitive edge and avoids the limits imposed by having a purely native supply of people," the report said.
Report author Katerina Rüdiger said, "Global firms need more global people - not just to fill shortages, but for the sake of enabling firms to innovate. The UK's best bet for making the most of globalisation is to tap the increasing flows of highly qualified people around the world."