The US singer and superstar will take to the stage in The Atrium at the shopping centre in Shepherd’s Bush on Thursday November 30.
The No Doubt frontwoman will be counting down to an amazing display of pyrotechnics and switching on the glittering Christmas lights before performing live.
The three-time Grammy award winner has sold more than 30 million albums worldwide, and her appearance at the festive celebration coincides with her "holiday album".
Back in October, Gwen realeased a Christmas album titled You Make it Feel Like Christmas, which features vocals from her country singer boyfriend, Blake Shelton.
In an interview when she was revealed as the face of the centre's Christmas campaign, Gwen said: "London is an amazing city all year round but there’s something magical about London during the festive season.
"The holidays are one of my favourite times of year and I am happy to be in London during the festive season, to share with you my new holiday album, You Make It Feel Like Christmas."
To attend the event and see Gwen, you will need an event wristband for the general viewing area.
These will be given out on Thursday November 30 at Westfield London before the celebrations, which began at 6pm.
For more information about attending the event, visit the website.
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