Croke Park bans backpacks for gigs and matches
Fans will no longer be able to bring large bags and backpacks into Croke Park.
New security measures have been implemented for all match days and concerts.
They have been scheduled to come into effect from this Sunday when Dublin face Westmeath in the Leinster Football Championship semi-final.
A statement from the GAA said the decision was made following a review of safety procedures with the relevant authorities.
Smaller bags will be permitted but may be subject to searches, it added.
Croke Park's website identified small bags as those no bigger than A4 (21cm x 29.7cm) size. Plastic bags smaller than A4 size will also be allowed.
Fans have been urged not to bring bags at all where possible in order to avoid delays.
As well as the latter stages of the GAA championships, Croke Park has been lined up to host concerts by Coldplay and U2 on July 8 and July 22 respectively.
The move follows a similar directive at the Aviva Stadium, where a 'no-bag' policy has been in operation since the recent international soccer friendlies against Uruguay and Austria.
The stadium has warned patrons may also be searched at the entrance to Croke Park, which may include a "full body" pat down and/or use of hand-held metal detectors.
Earlier this month, the GAA announced it was reviewing security arrangements at Croke Park ahead of a hectic four-month period when more than 750,000 people will attend games and concerts in the stadium.
The new measures come in the wake of the Manchester Arena atrocity, where 22 people were killed by a suicide bomber last month.
"We are continuously modifying and enhancing our security plans. We work very closely with gardai and the other statutory services at all times," said Croke Park stadium director Peter McKenna.
"We are always very conscious of security and will be enhancing that approach, but you have to be sensible in these situations as well.
"We plan for every eventuality that we possibly can but in a sensible way. We certainly don't want people to be fearful. We need to keep all this in context.
"The public can rest assured that our security arrangements are the very best they can be," Mr McKenna added.