According to the National Enquirer, the 'Womanizer' singer is in love with the Syco boss, who is trying to sign her up for The X Factor USA.
"Britney loves Simon - she's had a crush on him for years," a source claimed.
The insider added that Spears's fiancé Jason Trawick is aware of her feelings and "plans on sticking close to [her]" if she does join the show.
Her talks with X Factor network Fox are apparently in their final stages, with the 30-year-old set to sign imminently.
Several revelations about Cowell's love life have appeared this week, most notably his affair with former X Factor UK judge Dannii Minogue.
> Ten Things About... Britney Spears
Watch Britney Spears's 'Toxic' music video below: