The songstress and X Factor USA judge was spotted on Bedford Drive wearing no make-up as she ran errands in what appeared to be her gym kit.
She donned a grey hoody, leggings, a baseball cap and some sports trainers, while clutching on to a bottle of water and her designer purse.
It's no surprise that Kelly looked as though she was ready for a gym session, since the 32-year-old has a rock hard set of abs, which she has admitted to working hard for almost every day of the week.
And unlike some of her fellow celebs, Kelly doesn't seem to be a fan of slapping on the make-up while she's exercising.
On Monday (7 October), the former Destiny's Child star also looked a little different to her usual dressed up self, as she posed for a fun pic in a baggy tomboy ensemble.
The snap shows Kelly wearings trainers, baggy black trousers and a loose-fitting leather jumper, which has a zip at the side to flash a little skin.
She even added to her gangster-esque get-up by piling on the bling, with chunky gold rings and bracelets.
Kelly is currently starring on The X Factor USA after a successful stint as a judge on the UK version in 2011 and it sounds as though she is having a great time.
During a Twitter Q&A with her fans yesterday (8 October), she revealed that "hearing such incredible voices" was her favourite thing about being part of the show and she even referred to fellow judge Demi Lovato as her "girlfriend"!
What do you think of Kelly's tomboy look? Let us know below, as the best comment each week wins £50!