Most workers who reported sexual harassment to their employers said they were subsequently passed over for promotion - or became targets for more bullying.
The startling findings from a survey by the Irish Congress of Trade Unions (ICTU) also show that 81pc of people who experience sexual harassment at work don't report it to their employer.
Shockingly, it found that 27 of the respondents to the survey said they had been seriously assaulted or raped at work, with five saying the attacks had happened within the past year.
"Of all the alarming statistics thrown up by the polling, the fact that jumps out for me is the unacceptably high levels of under-reporting and dissatisfaction with their employer's action among those who do report sexual harassment," said ICTU general secretary Patricia King.
Of those who reported sexual harassment to their employer, three-quarters said that it had not been dealt with satisfactorily.
And in a damning indictment of how sexual harassment is often handled, 28pc of respondents feared they would not be believed, while 12pc thought they would be blamed if they reported the unwanted sexual behaviour to their employer.
The ICTU survey received replies from 1,347 members, 72pc of whom were women. It is publishing the survey to coincide with today's International Day for Elimination of Violence against Women.
"While the #MeToo movement has shed light on the hidden problem of sexual harassment and sexual assault in work and empowered women to speak out, the fear of a negative impact on their career or of not being believed or taken seriously were the most common reported reasons for not pursuing a complaint," said ICTU policy officer and lead researcher Laura Bambrick.
In relation to respondents, the survey found that:
As Christmas approaches, the survey found that work-related social events account for 20pc of the instances during which sexual harassment was reported by those surveyed.
Online sexual harassment is also playing a more prevalent role in the workplace, with 23pc of respondents to the ICTU survey saying they had received unwanted messages with material of a sexual nature by email, text, or over social media from colleagues.
"The Christmas party has long been identified as the most common off-site location of workplace sexual harassment, and this is borne out in our survey," added Ms Bambrick.
"However, the extent of unwanted sexual behaviour from colleagues taking place online also reported points to a growing problem in the modern workplace."
The survey found that 32pc of respondents who didn't report a sexual harassment incident feared doing so would negatively affect their working relationships. And 27pc thought doing so would have a negative impact on their career.
Employers have a legal obligation to prevent workplace sexual harassment, said Ms King.
Last week it was the turn of Steve Easterbrook - CEO of McDonald's - to be sacked for having a consensual relationship with a colleague. Last year Intel's chief executive Brian Krzanich resigned because of a similar breach, also consensual.
With a new drive against sexual misconduct taking hold at third-level institutions across the country, it might seem that student lad culture is becoming a thing of the past. But the ordeal of a female academic on one campus makes clear just how much work remains to be done.