Duncan Garrood has left Bill's Restaurants just 10 months after his appointment as CEO.
The former Punch Taverns chief executive had joined the restaurant group, owned by Richard Caring's Caprice Holdings, in January and was tasked with realising "ambitious growth plans".
Confirming his departure a spokesperson for Bill's said: "Duncan Garrood has decided to leave the business to focus on other ventures and new opportunities. The team will continue to be led by founder Bill Collison, executive chairman David Campbell and the existing management team as Bill's continues with its successful refurb programme across the country."
Garrood's is the latest in a string of departures from the group with industry veterans Andy Bassadone and Nick Fiddler having terminated their directorships earlier this year and former finance officer Greg Hinchcliffe leaving the company to join Caravan Restaurants.
Bill's saw an £8m boost in turnover last year but increases in underlying costs for food and labour costs due to increases in the National Minimum Wage and the devaluation of sterling following the EU referendum meant pre-tax profit was £4.8m, down from £7m the previous year.
Bill's was founded as a fresh produce store and café in Lewes, East Sussex, by greengrocer Bill Collison in 2000. There are now more than 80 restaurants across the UK.