Sales director Nick Miller will be taking over as managing director of the Peroni, Pilsner Urquell and Miller Genuine Draft producer's UK arm
from Oct 1.
Whitlie has been named managing director of SABMiller's Hungarian business, Dreher Breweries.
Miller joined Miller Brands in October 2005 and has
more than 20 years of industry experience.
He said: "I am delighted to accept the responsibility of leading the next chapter of success for Miller Brands. I am personally sad to see Gary go and I wish him every success in Hungary. "
Miller Brands is claiming 30% year-on-year sales growth in the UK, which it attributes to "consistent pricing and distribution discipline, engaging marketing activities, and bringing value back into the beer category".