Recent graduates are more likely to be working in lower-skilled jobs than they were 10 years ago, new figures suggest.
More than a third of recent graduates were in non-graduate jobs at the end of 2011 - up from about a quarter in 2001.
The figures, from Office for National Statistics, also suggest about a fifth of new graduates were unemployed.
TUC general secretary Brendan Barber called for an industrial strategy to reverse the trend of graduates taking low-skilled jobs.
Mr Barber said a lack of quality jobs had forced people with degrees into lower-skilled jobs. He said the government should focus on boosting high value industries such as manufacturing.
"Otherwise public investment in education and the talents of graduates will continue to be wasted," he added.
The study also calculates the typical wage of graduates aged between 21 and 64 to be just over £15 an hour - easily outstripping the average earnings of just under £9 an hour for non-graduates.
The figures suggest that the best-paid graduates of all ages are those with degrees in medicine and dentistry, earning an average of more than £21 an hour.
The lowest-paid graduates are those with degrees in the arts and humanities, who earn on average around £12 an hour.
The figures indicate that graduates are less likely to be unemployed than the rest of the available workforce.
At the end of 2011, the proportion of graduates of all ages who were in work stood at 86%, compared with 72.3% for non-graduates.
But the report says that since the recession began in 2008, the employment prospects of recent graduates have become more limited.
Twice as many new graduates were out of work at the end of last year as in 2008.
But the figures suggest that the employment prospects of new graduates may be improving slowly.
At the end of last year 18.9% of new graduates were out of work, compared with 20.5% at the peak of the recent recession.
The figures are also better than in the recession in the 1990s, when unemployment for new graduates peaked at 26.9% in 1993.
Universities and Science Minister David Willetts said: "A degree remains a good investment in the long term and is one of the best pathways to a good job and a rewarding career.
"Graduates, like everybody else, are facing tough times but the evidence shows they fare better than non-graduates and their prospects tend to pick up quicker during the recovery."
Carl Gilleard of the Association of Graduate Recruiters advised graduates to see any experience in the workplace as a valuable stepping stone towards their longer-term career goals.
Libby Hackett, director of University Alliance, called for universities to make the case for more higher education places as, despite the recession, the number of graduate vacancies continues to grow as a proportion of the total workforce.