The move, first reported by Caterer's restaurant blog Guide Girl, will see Drabble, who left the London Fine Dining Group in June, join the luxury 60-bedroom hotel on 1 September.
His appointment coincides with that of Christophe Thuilot, restaurant manager at the two-Michelin-starred Capital, who is joining St James's as food and beverage manager.
Drabble, who took over the reins at Aubergine from Gordon Ramsay in 1998, spent more than a decade behind the stove at the Chelsea restaurant. During this time he retained its Michelin star and successfully launched a sister restaurant in Marlow last autumn.
His remit at St James's will include the launch of a new restaurant, Seven Park Place by William Drabble, in the space formerly occupied by the three-Michelin-starred German chef Dieter Müller. The 25-cover restaurant, which will undergo a minor refurbishment, will serve a fine dining menu, with current head chef Phillip Vogel remaining behind the stove.
Drabble will also oversee a more casual restaurant, the 30-cover William's Bar & Bistro offering a classic menu, as well as the private dining and room service at the Mayfair hotel.
Drabble told Caterersearch he was looking forward to a new challenge. "Spending more than 10 years at the same place is a very long time and the moment was right for me to move on and do something different," he said.
"St James's is a nice sized hotel, it's a beautiful hotel, and all the opportunities are there for it to become something really special."
St James's managing director Henrik Muehle, who recently joined the property from the Capital and Levin hotels in Knightsbridge, said he was delighted to confirm Drabble's appointment.
"William's extensive experience of running Aubergine for ten years coupled with his knowledge of the London market makes him the ideal candidate for the role," he added.
By Kerstin Kühn
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