Matthews has been with Eblex since 1992 (when it was known as the Meat and Livestock Commission), and transferred to the newly-formed Agriculture & Horticulture Development Board (AHDB) in 2008.
He is an expert on carcase and meat quality, including classification developments, eating quality and other aspects of post-farm gate research.
Eblex sector director Nick Allen said: “Kim has a wealth of knowledge of the beef and sheep sectors, and has proved himself to be very capable of leading the department.
"Research and development is a fundamental part of the service we offer, and I am confident that Kim and his team will continue to deliver excellent value for money to our levy payers.”
Matthews said: “I am delighted to be taking on this role at such an exciting and challenging time for the beef and sheep sectors.
"There are plenty of challenges on the horizon, but Eblex is in a great position to equip English beef and sheep producers with the technical knowledge to improve their performance in a sustainable way.”
Matthews has served as interim head since October last year, when his predecessor, Dr Duncan Pullar, left to take up a role as sector director of DairyCo.