The former Girls Aloud star won't return to the ITV talent show as a judge later this year because she wants to focus on her music career as she is currently working on her new album.
In a statement released to Mail Online, Cheryl said: "I have had such an amazing experience being a judge on The X Factor. I have learnt so much and enjoyed nurturing talent but I've missed making music and am excited to be recording again. I want to thank everybody I have worked with along the way, especially Simon who I love to bits. I hope the show continues to produce stars and I wish them all the best."
Cheryl, who joined The X Factor in 2008, mentored two singers to victory - Alexandra Burke in 2008 and Joe McElderry in 2009.
She left the show in 2010 before rejoining in 2014.
Simon Cowell said of her exit: "Cheryl and myself spoke about this. I totally understand her commitment to making more records. She has been amazing on the show and in the near future we will be working on other things together."
Earlier, The Sun reported that Cheryl had informed show boss and close friend Simon of her decision to quit during dinner in Hollywood last week.
A source told the newspaper: "They have had many discussions about the new series but she finally made up her mind. Her relationship with Simon is the best it's ever been and they both are incredibly supportive of each other."
Are you sad to see Cheryl quit The X Factor?— Reveal Magazine (@RevealMag) April 5, 2016
Last year, Cheryl mentored the groups and took pop duo Reggie and Bollie to the final, where they finished in second place.
Cheryl was an executive producer on last year's series and she will reportedly continue to stick with the show in an advisory capacity, even vowing to return for a special live performance.
Cheryl, who is now dating One Direction star Liam Payne following her split from husband Jean-Bernard, is set to release her new studio album later this year, which will be a follow up to 2014's Only Human.
Cheryl's exit comes as Dermot O'Leary confirmed he will return to the show as the main host, after being replaced last year by Caroline Flack and Olly Murs.
Nick Grimshaw also quit as a judge, and it has been widely speculated that Rita Ora may not return.
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