Campbell, who was the Giants' footy boss for the past four seasons and has a contract for 2020, has been replaced by the club's list manager Jason McCartney.
"Jason's existing relationships with our playing group, coaching staff and wider football department staff sees him well placed to ensure a smooth leadership transition as we head towards the 2020 AFL and AFLW seasons," GWS chief executive Dave Matthews said.
"We wish Wayne Campbell the best for the future and thank him for his contribution since joining the club at the start of the 2016 AFL season."