The supermarket chain, which is due to finalise its £1.4 billion takeover of HRG in the third quarter of this year, said John Rogers will take charge of the business when the deal completes.
The moves come the day after Argos said it would have to shell out £30 million in compensation for over-charging store card customers.
Rogers, who has been the grocer’s chief financial officer since 2010, said: “The combination of Sainsbury’s and Argos is an exciting one for customers, colleagues and shareholders. I am delighted to have the opportunity to lead and work with the talented teams at HRG and to develop the business further as one of the UK’s leading retailers.”
Walden joined HRG in February 2012 as managing director of Argos and was promoted to group chief executive two years ago.
He said: “I believe the acquisition of the group by Sainsbury’s is in the best interests of our customers, colleagues and shareholders. However, this impending transaction, together with the recent sale of the Homebase business, presents the opportunity for me to reassess the next stage in my career.
“I have huge affection for both Argos and the group, so it is with mixed emotions that I will be stepping down from my role to pursue new career opportunities once the acquisition completes.”