Rowling has written seven Harry Potter books
A signed set of first edition Harry Potter books is expected to fetch up to £20,000 at an auction in Berkshire.
The set of seven hardbacks published by Bloomsbury goes on sale at Cameo Fine Art Auctioneers in Midgham on Tuesday.
Each illustrated cover has been signed by the celebrated author JK Rowling without a dedication.
Last month, a short Harry Potter prequel written by JK Rowling was sold at auction for £25,000 to raise money for charity following a bidding frenzy.
Charities English PEN, which works to promote literature, and Dyslexia Action, received donations from the sale.
In January this year, Ms Rowling donated a set of seven signed titles to raise cash for Portobello Rugby Club in Edinburgh after it burned down, raising £6,960.
Last December another of her stories, The Tales of Beedle the Bard, fetched £1.95m at auction.
Amazon bought the book, which was handwritten and illustrated by the author.
Only seven copies exist: six were given to Rowling's close friends and the seventh was auctioned to raise money for her charity, Children's Voice.