Almost one in five calls made to a parents' helpline are complaints about grown-up children living at home.
Their grievances include sons and daughters in their 20s bringing home partners, not getting up on time for work, and sponging off parents.
Ms Rita O'Reilly of Parentline said the number of calls was growing every year as more young adults opted to stay in the family home rather than pay high rents or mortgages.
"Some of the calls are quite severe and relate to the violent abuse of parents by their grown-up children," she said.
"But most complaints are to do with lifestyle where parents would have worked hard all their lives and are now looking at children with a lot more money than they ever had with a different approach to work, money and spending."
She said 16 per cent of calls to Parentline in 2002 were complaints about adult children living in the parental home - but that is increasing by 2 per cent every year.
Her comments came in the wake of a survey conducted on behalf of Newstalk 106, which found that one in five 21- to 40-year-olds in Dublin still live with their parents. Southsiders were more likely to live with their parents than northsiders, it found.
Ms O'Reilly said most of those still living at home did so to fund a better social life, angering parents who end up funding it. "The parents would have saved to buy their homes and their cars and lived frugally. The children will spend on credit cards - they will spend and then deal with the consequences later."