Only 1 in 10 students going to college come from disadvantaged backgrounds.
A new Higher Education Authority report, which is the first of its kind, has found UCD, UCC and RCSI have the most students from affluent backgrounds.
Medicine, economics and maths are the courses most likely to include those from advantaged areas.
The study also found that students from affluent areas are earning 30 percent more than those from less affluent areas just nine months after graduating from college and that university graduates earn more than people who attended institutes of technology.
Caitriona Ryan from the HEA says it highlights the importance of making access to college more equal: 'We really need a whole of education approach to supporting equity of access to higher education starting at pre-school all the way through and working with communities to raise aspirations and expectations.'