She says she's getting there: "I have a beginning, a middle and an end - you could read it all the way through and I know a lot of Harry Potter fans will say just give it to us.
"But I'm a perfectionist and I want a bit more time to tweak!"
The Order of the Phoenix will be as long as The Goblet of Fire and there are plenty of new things to keep fans engrossed.
There will be a new female Defence of the Dark Arts teacher and a new sorting hat song!
Don't believe what they say!
She also said people shouldn't believe everything written in newspapers and on websites about how far off the book is.
She says she's never had writer's block in her life and admits she's loving the writing.
Court case relief
JK has just won a court case against an US author who claimed JK has stolen some of her ideas.
She said: "I'm so relieved. This court case has dragged on for a few years - I'm a really happy woman today!"
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