The flame-haired Florence And The Machine frontwoman makes the revelation in the latest issue of Nylon magazine.
The 24-year-old singer tells the US magazine: 'I wanted to be a witch when I was a kid. I was obsessed with witchcraft.
'At school, me and my two friends had these spell books; I always wanted a more magical reality.”
She added: 'I had a little shrine at home and I did a spell to try and make the boy in the other class fall in love with me.'
The South London-born star also reveals that legendary US artist Andy Warhol was at her parents' wedding day.
Commenting on a photo from her mother and father's big day, featuring the late painter, she says: 'Look – He's got a camera around his neck.
'My dad always said that it meant that somewhere, there might be some pictures Andy Warhol took of them on their wedding day.'