Interim chief Geoff Babidge will himself step down in February to make way for new chief executive David Bortolussi, whose appointment was announced in August last year.
Bortolussi's most recent role was group president - International Innerwear, HanesBrands.
He joined Pacific Brands in 2009, initially as chief financial and operating officer taking over as CEO in 2014, during which he restructured and transformed the business.
He had previously spent five years at Foster's Group, where he held the role of chief strategy officer responsible for corporate strategy, mergers and acquisitions.
A2 Milk's share price has been under downward pressure due to Covid-driven disruption of the unofficial daigou trade channel from Australia to China.
The stock last traded at $11.50, well down on last year's high of $21.51.