But get this, the new book is not a Harry Potter spin-off.
In her tweet, Rowling says, over the past 10 years, she had invested her time in writing a standalone fairytale called "The Ickabog" but she never got around to publishing it.
She further stated that she thought of the book as just for her family. She kept the manuscript in the attic and almost forgot about it, up until now.
She also said that opening the box after so long took her back in time.
While sitting at home, over these past few weeks she made a few changes in the manuscript and decided to publish the book for free online so that children have something to keep themselves busy with, during the lockdown.
But, there's a twist. The author has requested participation from readers to illustrate it.
Well, this news has got Twitter all excited.
My heart almost stopped— Flávio Bessa Jr. 🇧🇷✊🏼🚫🐮 (@flaviobessajr) May 26, 2020
I love reading your books ma’am. You’re an inspiration 🥰— Andre (@gamermaniac25) May 26, 2020
Hell yeah! Bring it on. Are you excited?