Paul Turner has left his post as general manager (people) at West Bromwich Building Society after 30 years with the company.
His move came as Stephen Karle stepped up to become chief executive on 1 October, taking over from previous CEO Andrew Messenger, who has retired.
Turner, who has been in the top people role for the past decade, said he felt it was time to move on. "I am proud to be associated with the development of people strategies that have helped deliver an unprecedented set of results," he said.
"I believe the time is right for a change, and I look forward to new and exciting opportunities."
West Bromwich Building Society confirmed there had been a "senior management restructure" and "Paul has left by mutual consent".
Karle added: "Paul has been internationally recognised for his outstanding leadership and drive in developing our progressive people strategies. His energy, drive and enthusiasm have enabled the society to offer best practice in people development."
The company has not yet announced who will become its new HR chief.
Turner has won a series of major awards during his career, including Overall Winner at the Personnel Today Awards 2004.