Ireland West Airport in Knock has closed for the day.
Authorities said runway conditions are unsafe because of the freezing conditions.
Around 1,500 passengers are affected.
They are being advised to contact their airline for further information.
Managing Director Joe Gilmore said despite crews working around the clock to de-ice the runway, conditions have got the better of them today.
"We've had snowfall here since December 18," Mr Gilmore said. "We have operated effectively right through the Christmas - we've handled over 25,000 passengers - it's only in the last couple of days that we have been impacted by more severe weather conditions."