Mr Carpenter will take up the position of executive general manager, corporate affairs in early December.

Wesfarmers managing director Richard Goyder said he was delighted Mr Carpenter had decided to join the company.

"Alan is a very talented person, who, as a senior Minister and Premier, made a significant contribution to WA public life," Mr Goyder said.

Mr Carpenter said he was extremely pleased to be joining Wesfarmers.

"I think most West Australians, whether they are investors or not, have a very high regard for this company," Mr Carpenter said.

"This is probably because Wesfarmers has earned a deserved reputation as a company that has not only achieved sustained business success but is also respected for its integrity and community commitment."

In his role, Mr Carpenter will be responsible for the Group’s external affairs activities including media relations, government, community contribution and sustainability.