She’ll take up what’s arguably the most powerful job in domestic football anywhere in the world early in 2019.
Richard Scudamore, who has been executive chairman, will step down at the end of the year.
The Premier League clubs have already agreed to split his role, with Dinnage becoming chief executive, and the search for a non-executive chair will now begin.
Chelsea chairman Bruce Buck, who was in charge of the appointment process described her as the ” outstanding choice given her track record in managing complex businesses through transformation and digital disruption”.
JB Perrette, President and CEO Discovery Networks International, commented: “Susanna has been a terrific leader for Discovery over the last 10 years. She has a strong understanding of brands and running diverse media businesses both in the UK and more recently with Animal Planet globally.
Last November, Dinnage was appointed to the new role of global president, Animal Planet. Beforehand she was president of UK/Ireland and Chief Content Officer for Discovery Networks International.