Kelley, 51, will also become president and join the coffee company's board, effective Dec. 3, the Waterbury, Vt., company said Tuesday.
The stock is up 12 per cent in premarket trading.
Its current CEO, Lawrence Blanford, had said in February that he planned to retire.
Green Mountain Coffee pioneered single-serve coffee in the U.S. with its Keurig machines and grew quickly on their popularity. But the company has struggled, with shares down 39 per cent this year, as patents on technology for its K-Cups expired and competitors released their own single-serve coffee makers.