The form-fitting frock, from Victoria's autumn 2012 collection, features cute cuff detailing and a contrast collar.
Katherine is the latest star to step out in the design, which retails for around £1,650, wearing it outside ITV's London studios this afternoon (31 January).
She paired it with nude platforms and a taupe handbag for her take on daytime-chic.
Victoria worked the look in Beijing last year when she teamed it with thigh-high peeptoe boots and a voluminous ponytail.
But it's not just Posh and Katherine who have been rocking the look. Rochelle Humes donned a Missguided version in Los Angeles while Billie Faiers was spotted in a similar style on TOWIE!
It seems Katherine is a firm fan of Victoria's designs, having worn a red floor-length piece on Strictly Come Dancing (above) in December.
What do you think of Katherine's latest look? Tell us below as the best comment from across the site each week wins £50!
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