Community leaders feared that kids aged five and under who wanted to take along their pirate swords, witches' broomstick and Grim Reaper accessories to a 'spooky' school disco could hurt each other so were told to leave them at home.
Local mother Jo Turley told The Sun: "Please leave our kids alone and let them be kids. So long as they are supervised, where is the harm?"
The party was held yesterday afternoon at the Treuddyn Schools Campus, which is home to both Ysgol Parc y Llan Primary School and Ysgol Terrig Primary School, but was organised by a local playgroup.
Flintshire councillor Carolyn Thomas who helped organise the event said: "The children are very young and we just didn't want them running around with any pointy things.
"It was to save them hurting themselves or getting upset if they lose the articles."
The ban was in spite of posters publicising the event telling parents that under fours could not attend without an adult.