More than 100 witches and wizards attended the event at the multi-award winning theatre, independent cinema and library.
Activities included wand making, a sorting hat ceremony, potions class, wizard duelling, Beadle the Bard storytelling, a costume parade and themed arts and crafts.
Storyhouse library team leader Linda Tyson said: “It was such a wonderful event. A real feeling of being part of something special; a Potter community.
“Some of the costumes were truly incredible, and the enthusiasm was contagious – the entire building was fizzing.
“Storyhouse has such a fun community - where people come out and take part, get involved and feel part of something. It was just fabulous!”
Harry Potter book night is an annual event organised by book publishers Bloomsbury, and hosted in libraries across the world.
To find out more visit storyhouse.com.