The actress is making her Bollywood comeback with Koochie Koochie Hota Hai.
She told DNA India: "I'm an absolute books person, to the point of being called a bookworm.
"If there's one thing I can't do without, apart from my family of course, it's got to be books.
"Earlier it was impossible to catch me without a book in hand, but now I have to make an extra effort to take time out for reading."
The Om Shanti Om star added she preferred "light, frothy" novels over the "heavy" kinds.
Kajol recently came to the defence of fellow mother Aishwarya Rai-Bachchan, after the latter was criticised for putting on weight after pregnancy.