The study also found that 88 per cent "strongly disagree" with any relaxation of regulations that allows such providers access to public subsidies, while 81 per cent think that the expansion of the commercial sector would harm the reputation of UK higher education.
According to the report from the University and College Union, which surveyed 506 senior academics last month, there is an "overwhelming consensus" that an easing of restrictions on for-profit providers would put standards at risk.
More than four-fifths (85 per cent) of the professors questioned, who are all UCU members, say they think courses offered by for-profits would be of "lower quality" than those at publicly funded universities, while 79 per cent claim that employers would also take such a view.
The survey has been released ahead of the government's White Paper on the future of higher education, due to be published in the next few weeks, which is expected to lay out regulations on how the for-profit sector accesses public funds.
Currently, students on "designated courses" at some for-profits can access state loans, but ministers are known to be keen to extend this entitlement to encourage more competition within the higher education sector.
The UCU warns that there is a danger that the UK could experience the same problems as the US, where large for-profit institutions that rely on fees paid through student loans have been accused of mis-selling degrees.
The survey also found that 99 per cent of respondents believe that for-profit providers' degree-awarding powers should be subject to regular review. This is currently the case.
Almost as many (93 per cent) think that commercial providers should have the same obligations to widen participation as publicly funded institutions.
The report also quotes academics, including Daniel Waldram, professor of theoretical physics at Imperial College London. He said that the for-profit model was "wholly inappropriate for providing high-quality university education appropriate to the needs of the UK".