Between 2001 and the final quarter of 2011 the proportion of people graduating in the previous six years who were in low skilled jobs increased from 26.7 per cent to 35.9 per cent.
Over the same period the number of graduates in the labour market and no longer in education increased from 1,063,000 to 1,501,000.
Examples of jobs classed as low skilled by the ONS include postal workers, hotel porters, machine operators, retailers, and clerical and secretarial occupations.
Meanwhile, the ONS data show the average hourly wage for graduates is £15.18, 70 per cent higher than non-graduates. Arts graduates earned the least per hour on average (£12.06) while those with medicine and dentistry degrees earned the most (£21.29).
Graduates who left university most recently were more likely to be unemployed.
The unemployment rate for those who left in the last two years was 18.9 per cent, much higher than for graduates who left two to four years ago (6.7 per cent) or four to six years ago (4.4 per cent).
Carl Gilleard, chief executive of the Association of Graduate Recruiters, said the results demonstrated “the competitive nature of the graduate jobs market”.
He said that the figures showed the “vast increase in the size of the graduate population”, which was something that “must be taken into account when evaluating these statistics”.
Mr Gilleard advised graduates “to gain experience in the workplace and see it as a valuable stepping stone towards their longer term career goals.”
“AGR members believe a degree remains a valuable and worthwhile investment, and this report demonstrates this. Graduates are more likely to be employed and have higher average earnings than non-graduates, with median hourly earnings for graduates 70 per cent more than non-graduates,” he added.