The stars will feature in a print advertising and in-store campaign for its Autograph brand. The collection will be available in-store and online next month.
The signings are the latest indication that M&S is aiming to appeal to a younger consumer.
The retailer recently became the exclusive fashion partner of The X Factor, with M&S sponsoring the fashion section of the X Factor official website and previewing its autumn fashions on the site.
Steve Sharp, M&S executive director, says Reynolds and Huntington-Whiteley are the “perfect fit” for Autograph.
He adds: “It’s a very different campaign for M&S as it’s the first time that we have focussed on one of our brands in this way. We are very proud of the result – a set of truly stunning photographs that totally encapsulates the Autograph brand.”
M&S has also chosen model David Gandy as the face of its Collezione autumn collection.
M&S said Lisa Snowden, Jamie Redknapp and Twiggy continue to model for the brand and will appear in autumn print advertising and in-store marketing materials next month.