Waterstones in Sauchiehall Street and Argyle Street opened early at 8am to cope with the expected demand, and expressed delight at the number of pre-orders for The Casual Vacancy.
Copies of the book were delivered yester-day to bookstores across the country amid considerable secrecy, with booksellers under instructions to keep the books under lock and key until this morning.
James Aldridge, event co-ordinator, Scotland, at Waterstones, said of the chain's Sauchiehall Street store: "We've had a phenomenal number of pre-orders for the book and will open at 8am for our customers, but as to whether people will drop in early on their way to work or will wait until later on, we will have to wait and see.
"There's been a lot of anticipation from customers, a lot of questions about the book, as well as a lot of goodwill towards her hoping that the book is a great success.
"I think she's dear to a lot of people's hearts.
"Considering that the next few weeks see new books from people such as Jamie Oliver, Tulisa Contostavlos, Steven Gerrard, Terry Prat-chett, Cheryl Cole and Rod Stewart to name a few, the buzz surroun-ding Rowling's book has been great for what is essentially her first adult fiction book."
WH Smith in Argyle Street was opening today as usual at 7.30am and had the book on sale at 8am.
Pre-orders for The Casual Vacancy across the UK are said to have reached one million.
Rowling herself said of it: "I don't think everyone will like the book. But I'm proud of this book. I like this book. It's what it's meant to be. As an author, you can't say more than that."