Departing Four Corners presenter Kerry O'Brien has farewelled his audience while assuring viewers that he was not retiring from journalism.

The highly-acclaimed journalist has worked for the ABC for 32 years, anchoring flagship news programs Lateline, 7.30 and Four Corners.

O'Brien, who leaves Four Corners after five years, said he would turn his attention to writing a second book after recently completing Keating, a collection of conversations with former Australian prime minister Paul Keating.

"I've been privileged to enjoy a long and deeply fulfilling run with ABC current affairs programs over many years, and to have shared that journey with you. You are why we're here," he said on Monday night.

"And I've been massively privileged to have worked alongside so many of the best craftsmen and women our industry has produced - people dedicated to the pursuit of excellence. It should go without saying, but I'll say it anyway - the more complex our future as a nation becomes, the more vital the ABC is to that future.

"I'm not retiring from journalism, just moving onto other things. In the meantime, go well and goodnight."

O'Brien has won six Walkley awards for excellence in journalism, including the Gold Walkley and the Walkley for journalism leadership.

ABC Managing Director Mark Scott said the ABC audience "has known, trusted and respected Kerry O'Brien for decades".

"In recent years at Four Corners he was able to synthesise important and often complex stories in a way that helped audiences stay and appreciate the very best in Australian journalism.

"It has been a golden era at Four Corners, and Kerry has been a vital part of the team."

O'Brien announced he would leave Four Corners after five years in early November.