The PM was escorted from Da Nang International airport under heavy security to Novotel airport.
His first official engagement will be on November 10th, when he chairs a session with the 21 APEC leaders.
O’Neill will also have meetings with US President, Donald Trump, China and other leaders.
The Vietnamese President and chair of the APEC Summit 2017, Tran Dai Quang, will officially hand over the chair to O'Neill on Friday.
PNG will host the APEC Summit in 2018.