The Government has being urged to introduce rent controls in an effort to stabilise the market.
Rents have risen by 25% nationally since 2011, but by more than a third in Dublin.
The Peter McVerry Trust said that current supply problems and high rents are leaving many people homeless.
CEO of the charity Pat Doyle says it is out of control.
"We've seen rents going up 36% in Dublin since 2011, that's 17 times greater than the consumer price index, so that is way beyond market rent. That is out of control now, " said Mr Doyle.
"There's no way that social protection can keep up with that, there's no way that low-paid and vulnerable families, and young people coming out of care can keep up with those rent increases."