The Residential Landlords Association has criticised Minister for the Environment Alan Kelly over his commitment to tackle rising rents.
Speaking on RTÉ's Today with Sean O'Rourke, Fintan McNamara said Minister Kelly's pledge to implement rent control would result in a shortage of accommodation.
Mr McNamara called on the minister to amend the blanket ban on bedsits to address the housing crisis.
"If rent control comes in and the market is depressed many of those landlords will say 'to hell with it, I'm not going to bother with this anymore.
"It's not worth the effort'. In 2002, only 8% of the housing stock was privately rented," he said.
"It went up to 18% in 2011 and it could sharply fall again if draconian measures are introduced and are not thought out properly like the blanket ban on bedsits," Mr McNamara added.
Meanwhile, Focus Ireland has welcomed the commitment by Minister Kelly to take action on the issue of rising rents.
At the Labour Party conference at the weekend, the minister said he would bring proposals to Cabinet under which tenants would have their rents fixed and linked to the rate of inflations.
Landlords would also have to justify an increase in rents by refurbishing the property.
Some rent increases by landlords are "absolutely scandalous" and need to be brought to an end, Minister Kelly said.
Speaking on RTÉ’s Morning Ireland, Focus Ireland's Director of Advocacy Mike Allen said that due to increasing rents, 52 families had been forced out of the private rental market in January.
He said there needs to be urgent action on rent control due to a risk of landlords hiking rents in response to the minister's announcement.
"The people we're concerned about are at the bottom end of the market where they're struggling to get any home and they are not in a strong negotiating position.
"“So he [Minister Kelly] needs to introduce something which is mandatory and which covers everybody in the market and comes in very quickly," Mr Allen said.
"We recognise that this is a very complex issue and we're not just out to have a go at landlords.
"Landlords need to have a decent return on their income and we don't want to frighten them out of providing homes but we do need urgent balanced action on this from the minister," he added.