Walsh, who left the Guinness and Johnnie Walker maker Diageo in May after 13 years as boss, said he was “delighted” to be joining the Compass Group.
Walsh will take up the role on January 1 2014. He will also become a non-executive chairman after the annual general meeting on February 6 2014.
Sir Ian Robinson, senior independent director of Compass, said: "His experience leading one of the UK's largest international companies through a period of significant global expansion makes him an excellent choice, and we look forward to his valuable contribution to the business.”
Before taking up the chairman position at Diageo, Walsh held a number of senior executive roles, at Diageo in the UK and North America.
He is currently a non-executive director of FedEx Corporation, Unilever and Avanti Communications Group PLC.