Australia Post is appointing a chief mental health officer, the first government business enterprise to do so.

Group CEO Paul Graham says the move reflects the increasing recognition of the importance of mental health and Australia Post is helping drive the culture change.

The nation's postal service was focused not only on the physical safety of its staff but also on the mental health and wellbeing of its more than 60,000 extended workers, he said on Tuesday.

The size and scale of Australia Post gave the organisation a unique opportunity and a moral obligation to lead, he said.

"We will then be able to share those learnings to help the broader community," Mr Graham said.

The appointment will build on Australia Post's partnership with Beyond Blue, which connects Australian communities with important mental health initiatives.

Beyond Blue's mental health information has reached more than six million letterboxes across Australia, including four million prepaid postcards encouraging people to take action to support their mental health by writing to each other to connect.