Six-year-old Harry from Glasgow is dressed as Charlie Bucket
Roald Dahl Day takes place every year on 13 September.
Roald Dahl is one of the most famous authors in the world.
His books have been translated into 61 languages and have sold more than 250 million copies worldwide.
He died on 23 November 1990. But to celebrate all of the author's wonderful books, children dress up as their favourite characters for Roald Dahl Day.
We wanted you to send in photos of your amazing Roald Dahl Day costumes and you didn't disappoint.
Check out the great snaps below!
Six-year-old Gracie from Pembrokeshire is Mrs Twit
Three-year-old Jasper from Blackburn went to nursery dressed as Fantastic Mr Fox
Lucy from London as the Giraffe from 'The Giraffe and the Pelly and Me'
Sandness School in Shetland had good fun dressing up today
Six-year-old Freya from Worthing as Matilda
Maya is going to school dressed as Sophie from 'The BFG' holding her snozzcumber
Devvean from Manchester has got her own Roald Dahl Day t-shirt