The Gay and Lesbian Equality Network is to close following a review of its operations.
Glen said it cannot return to financial viability while maintaining services.
The charity was mired last month in controversy when it emerged that the Charities Regulator was looking into its finances and has requested three years of credit card statements and accounts.
It is understood that the Charities Regulator has not at this stage begun a statutory investigation.
Three employees are being made redundant.
Its outgoing executive director, Áine Duggan, resigned saying she raised financial issues and made the voluntary disclosure to the regulator.
One of its founders, Kieran Rose, also resigned from the organisation saying he regretted that he had not declared supports given by Glen to him during his Seanad campaign and he said he had paid back over €11,000.
Glen was set up in 1988 to promote gay rights and was a prominent backer of the 2015 Marriage Equality campaign.
The Health Service Executive had withheld some monies from Glen for 2017.
The author of the report into alleged financial irregularities at Glen said the charity was facing challenges on five different fronts.
Speaking RTÉ's Morning Ireland, former senator Jillian Van Turnhout said most organisations could weather one front, but not all five.
She paid tribute to the three staff working in the organisation.
Ms Van Turnhout stressed that there was no misappropriation of funds in Glen, but she described the use of credit cards at the charity as "incredibly poor practice", although it came from a good intention to not leave employees out of pocket if they paid for things for the organisation.
She said such credit cards should never be used for personal purposes.
She said the charity could attract funding for individual projects but could not get funding for its core activities, which meant it did not have a reserve fund.
Ms Van Turnhout said the organisation was under review from the Charity Regulator, not under investigation.
However, the second the controversy went public "not a cent" came in from funders to the organisation.
She said the board had always prioritised the community it serves and the helpline provided by Glen would continue.