A quarter of families say they find it difficult to make ends meet and 43% of them have cut back on basics.
The findings are contained in the Growing Up in Ireland study, which will be published later.
The study looks at how 5-year-olds and their families are faring across a range of areas, including the transition to school, well-being, and diet, along with family circumstances.
Research Professor at the ESRI, James Williams, is the Principal Investigator of the Growing Up in Ireland project - he says the study also shows that 20% of our 5-year-olds are overweight or obese:
The study also shows a high take-up on the free pre-school year, with a quarter of families saying they would not have been able to afford pre-school for their children had it not been made available: