Children can travel free of charge at weekends during February, March and April as part of a range of new fare initiatives by the National Trasnport Authoriy.
The offer covers both Luas lines and is available on Saturdays, Sundays and Bank Holidays.
Two children can travel free of charge with each adult who has a valid Luas adult ticket.
Luas carried a record 29.4 million passengers in 2012 and it is hoped that this free offer will encourage more customers to travel on the LUAS.
Minister for Transport, Tourism and Sport, Leo Varadkar welcomed the initiative and said: "This is a generous offer for families and represents really good value. With the Gathering Ireland 2013 already underway, it's also likely to be popular with tourists and I will be encouraging the tourism authorities to promote it with visitors. The offer will apply to anyone travelling with both regular tickets and Leap cards".
The offer will be available to the thousands of extra visitors expected for The Gathering celebrations, St Patrick's Day and the Easter holidays.