The number of new UK graduates working in jobs like cleaning or bar work has almost doubled to 10,000 in five years, according to government statistics.
The figures, from the Higher Education Statistics Agency, also showed more than 20,000 were still out of work six months after leaving university.
Overall the data showed 71% in work and a further 16% in continued study.
Universities Minister David Willetts said graduates were still doing better than people without degrees.
The figures showed 9% of new graduates were jobless six months after completing their degree in 2010/11.
This was the same proportion as the year before but almost double that for 2006/7 when the figure stood at 5%.
A further 5% were working in jobs such as labourer, courier, office junior, hospital porter, waiter/waitress, bar worker, cleaner or road sweeper - up from 3% five years ago.
The figures also showed a continuing rise in the numbers employed in sales and customer-service roles, such as sales assistant, market trader or call-centre staff - 20,675 (10%) of new graduates worked in these areas last year, a rise of more than 1,000 on the year before and up from 12,740 five years ago.
The figures showed the largest group, more than 47,000 people (23%), went into "associate professional and technical jobs", as nurses, paramedics, interpreters or laboratory technicians.
Graduates diversifying
Just over 10,000 (5%) went into management and just under 37,000 (17%) entered professions like law and medicine.
A separate survey of 1,000 students for the high street chain, Aldi, suggested only a quarter of UK under graduates expect to gain a job in their field of study.
