Harris, who was the club's inaugural signing in BBL Season 1 and played in the Heat's second championship season, will join Brisbane as a specialist bowling coach for the first half of the season. He will work alongside head coach Darren Lehmann and assistant coach James Hopes.
Harris will depart before end of the BBL to complete his duties as Australia's Under-19 coach for the ICC World Under-19 Youth Cup in South Africa early next year.
"We used Ryan as a bowling mentor early in the BBL when he was returning from injury, and I know Dan Vettori had him on his staff in a similar role a few years ago," said Lehmann.
Harris was a dominant figure for Australia as their pace bowler spearhead, claiming 113 Test scalps at 23.52 in a career curtailed by injury.
He played in the Indian Premier League (IPL) with Deccan Chargers and King's XI Punjab.
Since retiring in 2015, Harris has worked within Cricket Australia's High Performance coaching programme based at the Bupa National Cricket Centre and is currently Justin Langer's bowling coach with the Australian team during the Gillette T20 International series against Sri Lanka.
"I really enjoyed my time as a player with the Heat, and it was where I got an opportunity to dip my toe in the water with regards to coaching," Harris said.
"It's another great chance for me to improve my coaching experience with 'Boof' and get ready to work with some of the country's most talented young players at the Under-19 World Cup next year," he added.
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