After five seasons with the Eagles, Burns was an unsuccessful applicant for the senior position vacated by John Worsfold, finishing among the top three candidates.
He considered an offer to remain as part of new coach Adam Simpson's panel, but decided to return to the club for which he played 265 games and captained in the last of his 14 seasons.
"I have really enjoyed my time at the Eagles and appreciate the opportunities they have given me," Burns said.
"The chance to take up this position at Collingwood was too good to pass up and I’m looking forward to the next chapter.
"I’ve learnt a lot from so many people at the club and I’d like to thank them and wish them well for the future."
Football operations manager Craig Vozzo paid tribute to Burns who steered the Eagles' young midfield through a period of transition and strong development, saying his ability to motivate and educate the players had been outstanding.
Simpson's coaching panel at West Coast is yet to shape, with assistant coach David Teague and strategy and innovations coach Phillip Walsh leaving before the new coach's appointment.
Twitter: @AFL_Nathan