New figures from Permanent TSB and the ESRI show that house prices fell by 2.6% in the first six months of this year.
It is the first time there has been such a decline in half-yearly figures since 2001.
The house price index shows that the average price paid for a house in June was €302,605, a drop of just over €8,000 since the start of the year.
However, the ESRI has said the economy remains buoyant.
Meanwhile, figures from the Central Statistics Office show that construction employment in June fell by 1.1% compared with the same month last year.
It was the third annual drop in a row in the employment index, which covers private construction firms employing five or more people.
