Locals had complained that stressful and disturbing noise from planes was preventing people from sleeping.
Dublin Airport has been given six weeks to cut the number of night flights, following complaints by residents near the facility.
Fingal County Council's issued an enforcement notice which found the number of night time flights currently operating at Dublin Airport amount to an 'unathorised development'
It says the summer schedule which is being carried out is in breach of the limit applied as a planning condition.
Locals had complained that stressful and disturbing noise from planes was preventing people from sleeping.
DAA now has six weeks to reduce the number of flights at night to an average of 65.
In a statement the operators of the airport says it is disappointed at the decision to give 6 weeks notice to reduce the number of flights between 11 pm and 7 am.
It wants the local authority to suspend what it calls these 'overly onerous conditions'

Newbridge Scientist Hopeful For Ambitious Project Aimed At Preventing Hospital-Acquired Infections
Irish Rail To Scrap IT System Believed To Be Worth €50 Million
28,000 Calls To Newbridge Samaritans Centre In 2025
Kildare TD Calls For Prevention Of Supermarkets Disposing Of Unsold Edible Food
Talks Continue This Morning In Ambulance Staff Pay Dispute
Almost 1,800 Complaints Made To Ombudsman for Children Last Year
Man Dies Following Assault In Blanchardstown On Sunday
Value Of Unused Medication Each Year Estimated At Over €37.5M