EPA says some bird species are under threat, and air quality doesn't meet WHO standards in some urban areas.
It says littering remains a big problem, and the number of very clean rivers in Ireland has fallen by 96 per cent in the past 30 years.
Dr Jonathan Derham, from the EPA, says the new report highlights several serious issues.
"The principal challenge is we have made some progress in limited areas, but poor progress in quite a number of others, whether it's on water treatment, air quality, biodiversity and I... Our view is, really one of the challenges is that we don't have an integrated, or kind of overarching environmental policy for Ireland."
