It will be the second stint at the 61-bedroom hotel for Sullivan, having previously been the property's senior sous chef.
In May it was announced that Hong Kong-based Swire Properties would be selling the hotel along with sister property, the 59-bedroom Magdalen Chapter in Exeter and two other hotels, the Avon Gorge hotel in Bristol and Hotel Seattle in Brighton. Property agent Christie + Co was appointed to handle the sale.
Sullivan, who replaces Gary Wheeler, said: "I am absolutely over the moon to be heading up such a brilliant and well established Cheltenham foodie hotel. I can't wait to get stuck in and start putting my own creativity into the menu.
"Having spent time working here as senior sous chef previously, I have been able to hit the ground running when it comes to getting under the skin of the Montpellier Chapter and its diners. I hope to bring a fresh stamp to the hotel, while still serving the flavours and dishes our guests know and love."
Until earlier this year Sullivan was executive chef at the Kings Head hotel, which opened in Cirencester in September 2014. He has also worked as head chef at the Parkers Brasserie, Cheltenham, as well as consultant chef with a number of other properties in the Cotswolds including Calcot Manor, Tetbury; Wesley House, Winchcombe; Hotel du Vin, Cheltenham; and the Bell at Sapperton.
Earlier in his career, Sullivan spent time at Marcus Wareing's Petrus in London, and the Wheatleigh hotel in Massachusetts, USA.
Sullivan will oversee the service of all food in the hotel's Restaurant, Garden Room, Terrace and Courtyard.
The Montpellier Chapter launched in 2010, when Brian Williams, managing director of Swire Hotels, announced plans to open a host of Chapter Hotels across prime UK towns and cities.
Swire Properties to sell two Chapter hotels >>Wayne Sullivan appointed executive chef of King's Head in Cirencester >>Chapter Hotels - the story of the launch >>Looking for a job? See all the current hotel vacancies available with The Caterer Jobs >>
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