Wood was previously the firm's global talent and organisational effectiveness director. She will take over from outgoing HR director Gareth Williams at the end of this month.
Ivan Menezes, chief operating officer of Diageo, said: "I am delighted to welcome Leanne to her new role. Leanne has a great track record across both strategy and HR, and wide experience of our business, having held roles in Ireland, South East Asia, Africa and our global functions."
Williams will remain with the company until June 2014, supporting a number of key projects.
