The Big Bang Theory star, who is engaged to tennis ace Ryan Sweeting, took to Twitter last night (10 November) to quash any speculation.
We're not exactly sure how the rumours started but Kaley certainly didn't hold back in her tweet!
She declared: "I would like to make something very clear to anyone who cares. I AM NOT EFFING PREGNANT. Do with that what you will."
Ryan proposed to Kaley in September after a whirlwind three-month romance. The couple even took part in a fake wedding on The Ellen DeGeneres Show, earlier this month, where they said 'I Do' in front of a studio audience.
Kaley admitted to Ellen: "I am so happy, life is so good right now." She also recently revealed that the pair are aiming for a wedding in early 2014.
Check out more engaged stars in the gallery below:
Copyright: Instagram Mark Wright