The APPEA CEO will leave his role in March - two months before APPEA's annual conference - to become vice president of government relations and public policy at BHP.
Byers will replace Christian Bennett at the mining giant, who is moving on to work for GE Oil and Gas.
His new role will see Byers report to BHP corporate affairs president Tony Cudmore, with whom he previously worked at ExxonMobil.
"David has made a valuable contribution to APPEA and he has been an extremely effective advocate for our industry," APPEA chairman Bruce Lake said.
"The past few years have been a time of great change and growth, both for APPEA and the oil and gas industry.
"The APPEA board thanks David for his dedication. The association is committed to continuing the excellent work under way to deliver the safe and environmentally responsible development of the nation's oil and gas resources."
Byers joined the lobby in 2011, replacing Belinda Robinson, and spent a great deal of his time dealing with east coast challenges.
High on APPEA's agenda in recent years has been the fledgling coal seam gas industry in Queensland, the Victorian ban on onshore drilling and fraccing and growing opposition to the industry in regional New South Wales.
Also underscoring the outgoing chief's time has been the rapid development of LNG projects around the country and the skills development it has demanded domestically.
APPEA said it had begun its recruitment process for a replacement.
