An annual survey of university graduates has found the smallest portion of graduates working in full-time jobs in two decades.

Only 71 per cent of bachelor graduates found a full-time job within four months, with the highest portion of unemployed graduates since 1994, according to a Sky News report.

• Unemployment rate rises to six per cent, despite new jobs

The GradStats survey of 100,000 graduates, conducted by Graduate Careers Australia, reported a deterioration in employment prospects for graduates, with 76 per cent securing full time employment in 2012.

These figures are the worst for graduates since the 1992-1993 recession.

Of those looking for full-time work, only seven in 10 graduates managed to find it.

According to the study, more graduates are also working in part-time and casual jobs and not looking for full-time work than any time since 2004.

Graduate Careers Australia executive director Noel Edge said that long-term prospects for graduates were still strong, with unemployment rates for graduates at 3.4 per cent – half the rate of those with no higher education.

In positive news, the survey reports that graduate salaries increased marginally from an average of $52,000 in 2012, to $52,500 in 2013.

Dentistry graduates remain the highest paid, with an average salary of $80,000 per year.