The 45-year-old, nicknamed The Body, will preside over the reality show, in which 25 aspiring models compete for a modelling contract.
The series is a spin-off of the runway hit America's Next Top Model. Created and hosted by Tyra Banks, the show is about to start its 14th US series.
Macpherson's lingerie line previously featured in the show's photo shoots.
In a statement, Elle Macpherson said, "I am really enthusiastic and motivated to work with the team of Britain's Next Top Model. We are looking forward to finding the face that can represent the next generation."