He had been enjoying a day out at the National Aquatic Centre in Blanchardstown when the incident happened. He was rushed to the nearby Connolly Hospital after being found in the pool but tragically later died.
A Garda spokesman has appealed for witnesses to the heartbreaking event which happened around 6pm yesterday evening.
The centre have now closed the Aqua Zone family pool until further notice.
Barry O'Brien, chief executive of the National Sports Campus Development Authority which runs the centre told the Independent that investigations were continuing into the little boy's death.
"We want to convey our deepest sympathies to the family of the boy," he said.
"Gardai are conducting an investigation into the incident with which we are co-operating fully."
Trained first aid staff at the aquatic centre are thought to have attended to the youngster at the poolside after he was found in the water.
Such a terrible waste of life. Poor little boy.
Do you worry about family trips to pools and water parks?