After 6pm the fear factor will be amped up, for older children.
The cost will be a gold coin donation, to cover costs, and any child under 12 must be accompanied by an adult.
Children will have a chance to pose for photographs and be given a choice of treats at the end of their fright session.
The show is put on by museum staff, and volunteers rostered to help out on the night.
Ms King-Wall said staff had help and costumes from Mainstreet Whanganui, which used to put on a Halloween trick or treat night downtown, but no longer does.
Halloween Night at the Museum is for everyone. Anyone who needs help with access can get it by ringing the museum on 349 110 during working hours.