Fare of London has won a three year contract at the Honourable Artillery Company (HAC).
Previously held by Crown Group, the deal will see Fare of London cater for around 800 events a year at the venue in the City of London.
The caterer will also work with the venue to sell its event spaces, which include the 18th-century Armoury House, the Prince Consort Rooms and the five-acre Artillery Garden.
Fare of London managing director John Durden said: "It's been a busy few months here at Fare of London and we are absolutely delighted that we were selected by the HAC. We work with a number of venues in the city and the whole team at Fare of London are truly excited to be working with such a richly historic and characterful venue as the HAC."
HAC head of marketing and events Diane Waldron added: "Fare of London have a proven track record of success with their existing clients and were selected on account of their reputation for quality cuisine and impeccable service which will match very well with the HAC's own high standards."