The 25 year-old joins from a role as chef de cuisine at the one Michelin-starred Restaurant Kong Hans Kaelder in Copenhagen.
He began his career at the Bath Priory Hotel, before moving on to Restaurant Sat Bains in Nottingham and the three Michelin-starred Benu in San Francisco.
His appointment follows last week’s announcement that Burge had left Whatley Manor after 13 years to pursue ‘new challenges’.
Keating will begin his role from 1 December, overseeing the hotel’s entire food and beverage operation including the two Michelin-starred Dining Room restaurant.
He will introduce his own menus from 14 January 2017, following the festive season and a brief closure of the restaurants from 8-13 January.
Sue Williams, general manager at Whatley Manor, said: “We are delighted that Niall has chosen Whatley Manor for his return to the UK.
“When I first met him at the Bath Priory his talent was immediately evident, and I have really enjoyed watching his career gather momentum.”
Keating thanked Williams and Whatley Manor owner Christian Landolt for the ‘fantastic opportunity’.
“[This] is an exciting next step for me, and I look forward to evolving the cuisine at Whatley Manor,” he said.