More than a third of recent graduates do not think their degree was good value for money, according to a poll.
It also suggests that many adults who have been to university say they would be unlikely to make the same decision under the current funding system.
The Edge Foundation, which commissioned the survey, argued it was no longer the case for many young people that a degree was automatically a passport to a good job and high salary.
Of those polled who graduated since 2010, 35% said they thought their degree was poor value for money.
And among all of the more than 2,000 graduates surveyed, 52% said they would be unlikely to go to university now, under the current funding system.
Students starting undergraduate courses at English universities this autumn pay up to £9,250 a year for their course. Government loans are available to cover the cost of tuition fees, which is paid back once a graduate is earning at least £21,000 a year.
Last month, the Government confirmed the salary repayment threshold was to rise to £25,000 a year, a move that ministers said would benefit about 600,000 borrowers in 2018/19.
Tuition fees have also been frozen at £9,250 for next year.
The poll found that 9% believe these changes, first announced by the Prime Minister at the Conservative party conference, will increase the value for money of degrees.
Alice Barnard, Edge chief executive, said: "This report shows that thousands of graduates feel that they have received poor value for money.
"All degrees are marketed as the passport to a good job, career progression and a high salary, but the disappointing reality for many is low-skilled employment and the burden of over £50,000 of debt.
"This hits young people from disadvantaged backgrounds particularly hard.
"Our survey showed that the thing which people value most from their time at university are the transferable skills that count in the workplace, but these are aptitudes and competences which can be acquired via apprenticeships or other opportunities.
"Graduates are rightfully concerned that the return on their investment can be so low.
"Encouraging much stronger links between higher education and employers can add value to students' studies, helping them to get the jobs they want and shape the careers they aspire to."
A study by the Institute for Fiscal Studies (IFS), a leading economic think tank, published last year, found there had not been an overall decline in the "graduate wage premium" - higher earnings associated with having a degree.
This was because firms had used the increased supply of highly-educated workers to change the way they operated, which had created more graduate jobs and left the wage premium unchanged.
But the study also said there were signs that this may be reaching an end, and further increases in the number of graduates going into the workplace could start to erode the wage premium in the future.
This did not mean it would not be worth getting a degree, but that the gains may be smaller, it said.
:: The YouGov poll questioned 2,015 adults with a degree in England and Wales between October 20 and 25.